System for extended key actions and haptic feedback and optimized key layout for a solid-state keyboard and touchpad

ABSTRACT

A haptic keyboard of an information handling system may comprise a coversheet to identify an extended action key of the haptic keyboard, a support layer, a contact foil, and piezoelectric elements placed between the contact foil and support layer to receive an applied mechanical stress at the extended action key and generate an electric actuation signal. A controller may receive the electric actuation signal from a piezoelectric element placed under the mechanical stress, via the contact foil, and determine the level of mechanical stress applied to the piezoelectric element from the electric actuation signal to select an alphanumeric character from a plurality of alphanumeric characters based on the mechanical stress level applied to the extended action key and provide a response haptic feedback control signal to cause the piezoelectric element to generate haptic feedback.

This application is a continuation of prior application Ser. No.16/779,575, entitled “SYSTEM FOR EXTENDED KEY ACTIONS AND HAPTICFEEDBACK AND OPTIMIZED KEY LAYOUT FOR A SOLID-STATE KEYBOARD ANDTOUCHPAD,” filed on Jan. 31, 2020, which is assigned to the currentassignee hereof and is incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to a key switch assembly of,for example, an information handling system. The present disclosure morespecifically relates to the use of piezoelectric sensor and hapticgenerator elements in a keyboard and touchpad of an information handlingsystem with extended key actions.

BACKGROUND

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option available to clients is information handling systems. Aninformation handling system generally processes, compiles, stores,and/or communicates information or data for business, personal, or otherpurposes thereby allowing clients to take advantage of the value of theinformation. Because technology and information handling may varybetween different clients or applications, information handling systemsmay also vary regarding what information is handled, how the informationis handled, how much information is processed, stored, or communicated,and how quickly and efficiently the information may be processed,stored, or communicated. The variations in information handling systemsallow for information handling systems to be general or configured for aspecific client or specific use, such as e-commerce, financialtransaction processing, airline reservations, enterprise data storage,or global communications. In addition, information handling systems mayinclude a variety of hardware and software components that may beconfigured to process, store, and communicate information and mayinclude one or more computer systems, data storage systems, andnetworking systems. The information handling system may includetelecommunication, network communication, and video communicationcapabilities. Further, the information handling system may include akeyboard or other input or output devices such as cursor control devicesfor manual input of information by the user.

BRIEF DESCRIPTION OF THE DRAWINGS

It will be appreciated that for simplicity and clarity of illustration,elements illustrated in the Figures are not necessarily drawn to scale.For example, the dimensions of some elements may be exaggerated relativeto other elements. Embodiments incorporating teachings of the presentdisclosure are shown and described with respect to the drawings herein,in which:

FIG. 1 is a block diagram illustrating an information handling systemaccording to an embodiment of the present disclosure;

FIG. 2 is a perspective graphical diagram of an information handlingsystem with a haptic feedback control system for a keyboard or touchpadaccording to an embodiment of the present disclosure;

FIG. 3A is a side cut-out view of a key of a keyboard implementing apiezoelectric element in an unactuated state according to an embodimentof the present disclosure;

FIG. 3B is an enlarged side cut-out view of a key of a keyboardimplementing a piezoelectric element in an actuated state according toan embodiment of the present disclosure;

FIG. 3C is an enlarged side cut-out view of a key of a keyboardimplementing a piezoelectric element in another extended actuated stateaccording to an embodiment of the present disclosure;

FIG. 3D is a side cut-out view of a key of a keyboard implementing apiezoelectric element in a downward warped position according to anembodiment of the present disclosure;

FIG. 3E is a side cut-out view of a key of a keyboard implementing apiezoelectric element in an upward warped position according to anembodiment of the present disclosure;

FIG. 4 is an exploded perspective view of a keyboard stack up for of aninformation handling system according to an embodiment of the presentdisclosure;

FIG. 5 is a series of sequential graphical views depicting a manufactureprocess of a coversheet of a keyboard according to an embodiment of thepresent disclosure;

FIG. 6 is an exploded perspective view of a touchpad stack up for aninformation handling system according to another embodiment of thepresent disclosure;

FIG. 7 is back perspective view of a C-cover of an information handlingsystem according to an embodiment of the present disclosure;

FIG. 8 is a top view of a piezoelectric element according to anembodiment of the present disclosure;

FIG. 9 is a top view of a contact foil of a touchpad for an informationhandling system embodiment of the present disclosure;

FIG. 10 is a perspective graphical diagram of an information handlingsystem with an optimized keyboard layout due with extended key actionsaccording to an embodiment of the present disclosure;

FIG. 11 is a flow diagram illustrating a method of operating a keyboardof an information handling system with extended key actions according toan embodiment of the present disclosure; and

FIG. 12 is a flow diagram illustrating a method of operating a touchpadof an information handling system with extended touchpad actionsaccording to an embodiment of the present disclosure.

The use of the same reference symbols in different drawings may indicatesimilar or identical items.

DETAILED DESCRIPTION OF THE DRAWINGS

The following description in combination with the Figures is provided toassist in understanding the teachings disclosed herein. The descriptionis focused on specific implementations and embodiments of the teachings,and is provided to assist in describing the teachings. This focus shouldnot be interpreted as a limitation on the scope or applicability of theteachings.

Embodiments of the present disclosure provide for a keyboard of aninformation handling system. The keyboard may include, in an embodiment,a coversheet to identify an actuation location of an input actuationdevice. The actuation location may designate one or more extended actionkeys in the haptic keyboard of embodiments of the present disclosure. Inan embodiment a support layer may be placed underneath the coversheet tosupport the coversheet and other layers within the keyboard. Thekeyboard may, in an embodiment, include a contact foil placed betweenthe coversheet and support layer. In the embodiments presented herein,the keyboard may include a piezoelectric element placed between thecontact foil and support layer to receive an applied mechanical stressat the actuation location of the input actuation device. The keyboard ofthe information handling system, in an embodiment, may include acontroller of the information handling system operatively coupled to thecontact foil to receive an electric charge at a plurality of levels ofcharge as one or more actuation signals indicating actuation of one ormore key locations from the piezoelectric element placed under themechanical stress. The mechanical stress may be applied to an extendedaction key at a plurality of levels of downward force to select from aplurality of alphanumeric characters or functions associated with thatextended action key in some embodiments. The controller may send one ormore electrical haptic feedback control signals in response to thepiezoelectric element. The one or more electrical haptic feedbackcontrol signals each provide varying in polarity, voltage or current tocause the piezoelectric element to provide haptic feedback at theactuation location (e.g., the extended action key). The one or moreelectrical haptic feedback control signals may correspond to one or moretypes of haptic feedback at the actuation location of the extendedaction key according to some embodiments herein.

According to embodiments herein, a haptic touchpad embodiment may worksimilarly with a coversheet under which a contact foil with an array ofpiezoelectric elements are electrically coupled may receive mechanicalstress from downward pressure on the coversheet interface surface of thehaptic touchpad. The haptic touchpad of present embodiments may furtherinclude a capacitive touch layer under the coversheet to detect X-Ylocations of touch or gestures across the coversheet of the haptictouchpad in embodiments herein. Pressure down on the coversheet of thehaptic touchpad may compress one or more piezoelectric elements in thearray of touchpad piezoelectric elements to generate one or moreelectric charges which may provide one or more levels of electric chargeactuation signals to a controller via the contact foil layer. As such,the haptic touchpad may detect plural levels of mechanical stress fromlevels of downward force applied to an extended action touchpad whichmay be used to select a function form a plurality of available functionsor a continuous change to a function due to selection by actuation bythe extended action touchpad.

Thus, each extended action key of the haptic keyboard of the embodimentsherein may have multi-level function for plural actuation pressurelevels applied to elicit plural electric charge actuation signal levels.These plural electric charge actuation signal levels may correspond tomultiple alphanumeric characters or multiple functions of the extendedaction key associated with the change of actuation pressure levelapplied reaching plural thresholds. Similarly, the haptic extendedaction touchpad may have multi-level function for plural actuationpressure levels as well in embodiments herein. The available functionsof the multi-level functionality of the haptic extended action touchpadmay depend on the X-Y location of actuation on the haptic touchpad insome embodiments. In some example embodiments, the multi-level functioncapability of the extended action keys of haptic keyboards according toembodiments herein may add functionality for each key to replace shiftor alt keys or may add to functionality available with shift and altkeys. The extended action keys of embodiments of disclosures herein mayenable streamlining or optimization of keyboard layouts such as withfewer needed keys in a QWERTY-type keyboard for example. Further, thecontroller system may provide multiple types of haptic feedback to thepiezoelectric elements associated with the extended action key ortouchpad actuation location. The multiple types of haptic feedbackevents may correspond to the multiple levels of actuation pressurereceived and indicate which of the multi-level functions, such asmultiple alphanumeric characters, has been selected by the useractuating the extended action key or extended action touchpad in someembodiments. In particular embodiments, the same piezoelectric elementor elements actuated may provide multiple levels of actuation signalelectric charge and also receive the haptic feedback control signal orsignals returned to generate the one or more types of haptic feedbackevents. As the haptic feedback control signal is modified, so to is thehaptic feedback event generated by the piezoelectric elements at theactuated extended action key or extended action touchpad location.

The use of piezoelectric elements within the keyboard may eliminate theuse of other devices such as a scissor mechanism that are used tomaintain a keycap of a key above an electrical connection or for a diveboard type mechanism under a touchpad. Instead, the piezoelectricelements may reduce or eliminate those mechanical elements that may failafter a number of actuations while also reducing the thickness of thekeyboard or the touchpad itself. Instead of the keys of the keyboardrequiring travel of a scissor mechanism within a C-cover of theinformation handling system, the relatively thinner keys defined (eitherphysically or visibly) on the solid state keyboard of thepresently-described information handling system may reduce the physicalthickness of the keyboard within the information handling system.Further, the solid state touchpad may eliminate the dive board mechanismand underlying click switch for selection of items via the mechanicallyactuated touchpad. This may enable a thinner, more streamlinedinformation handling system. The overall thickness of the informationhandling system may be reduced to as to decrease the size and weight ofthe information handling system. In other embodiments, because thekeyboard described herein has a reduced thickness, the space within theinformation handling system used to house other components, such as abattery, of the information handling system may be increased allowingfor the increase in size of these components or the inclusion ofadditional components within the chassis of the information handlingsystem. Additionally, because the solid state keyboard or touchpaddescribed herein does not include the mechanical components (i.e.,scissor mechanism and coupled key cap or dive board mechanism) as otherkeyboards or touchpads, the keyboard may be less susceptible to wear ormechanical strain over time. Instead, with the implementation of thepiezoelectric elements, the solid state keyboard or touchpad ofembodiments herein uses fewer mechanical parts and may be more robustresulting in longer usable life.

During operation of the solid state keyboard or touchpad of theinformation handling system described in embodiments herein, a key, suchas an extended action key, on the keyboard or the extended actiontouchpad may be actuated by a user pressing down on a specific location.As described herein, multiple levels of downward pressure thresholds maybe used to select among multilevel functions associated with theextended action key or extended action touchpad location. In anembodiment, this specific location may be visually indicated by aplurality of alphanumeric symbols or a function key symbol from whichmultiple functions may be selected via display of the selected functionon the display screen. The visual indicators may be similar to thosefound on a QWERTY keyboard or may utilize a more optimized keyboardextended action key layout enabled by the multilevel functionality.Visual indicators may include painted or marked locations, a keypedestal or raised location, or another designation such as a tactileframe or depression in a cover sheet. In an embodiment, this specificlocation may be a position on a touchpad user interface surface and mayalso have an x-y location detected by a capacitive touchpad interface.The actuations of these specific locations by, for example, a user'sfinger causes a mechanical stress to be applied to the piezoelectricelement resulting in the deformation of the piezoelectric element. Uponapplication of this mechanical stress and the deformation of thepiezoelectric element, the piezoelectric element accumulates an electriccharge that is passed to a controller of the information handling systemvia the contact foil described herein. The level of electric charge inthe actuation signal to the controller may reach plural threshold levelswhich may indicate or cause selection among levels of functionassociated with the actuation location at the extended action key orextended action touchpad. In other embodiments, key pressure thresholdsmay indicate continuous multiple levels of function among the plural keythresholds such as selecting gaming acceleration in gaming applicationsfor certain extended action keys of embodiments herein. Each thresholdof deformation and resulting electrical charge actuation signalmagnitude may correspond to an associated function such as designationof an actuating keystroke with multiple alphanumeric characters orfunction keys or another level of function within an application such asan increased movement or acceleration in gaming.

In an embodiment, the controller receives the electrical chargeactuation signal and sends an electrical haptic feedback control signalback to the piezoelectric element. In further embodiments herein,depending on the selected function among the multilevel functionsassociated with the actuation location or the continuous level offunction changed with increasingly applied pressure of an applicationfunction, a corresponding different haptic feedback control signal maybe sent. Upon application of the haptic feedback control signal on thepiezoelectric element by the controller, the piezoelectric element maybe mechanically stretched or compressed so as to create a hapticfeedback event by causing the piezoelectric element warping up or downand with varying magnitude, sharpness, or frequency and then returningto its pre-deformed state. This warping of the layers of thepiezoelectric element causes the user to feel a haptic sensation at theactuated key or the specific location where the user pressed in order toactuate an extended action key or extended action touchpad. Withdiffering haptic feedback control signals, different haptic sensationsmay be sent to the actuation location depending on the function selectedby the pressure level from among the plurality of functions orcontinuous change to function level associated with the actuationlocation. This haptic feedback against the user's finger may cause asensation of pressing a mechanical key thereby creating a feeling to auser that the extended action key was pressed or that the extendedaction touchpad has been clicked to select an item such as one displayedon a display screen. A second level of haptic feedback for a secondlevel of selected function may vary this feeling that a key has beenpressed by providing a burst of vibration, imitating a pause then deeperpress feeling, a bump or click, or multiple clicks in various exampleembodiments. It is understood that some keys on the haptic keyboard ofembodiments herein may be extended action keys while other keys may nothave extended actions in some embodiments. Further, some portions of thehaptic touchpad of embodiments herein may be an extended action touchpadwhile other portions may not in embodiments herein. Further, one or bothof the haptic keyboard or haptic touchpad may not be extended actiondevices in some embodiments herein.

Embodiments of the present disclosure employ piezoelectric elements inorder to provide haptic feedback at a thin keyboard or touchpad. In thepresent specification and in the appended claims, the term “actuate” or“actuation” is meant to understood as an action that causes anoperation. In the context of the present disclosure, this includes theaction by a user such as pressing against a location on a keyboard ortouchpad. During actuation of a key or touchpad, a user may pressagainst a visually labeled or tactilely identified key on a keyboard oran unlabeled or labeled location on a touchpad or touchpad area of aC-cover. This actuation, according to the present disclosure, causes amechanical strain on a piezoelectric element and, consequently, cause abuildup of electric charge in the piezoelectric element. This electriccharge is detectable by a controller via a conductive contact foil. Thedetected electrical charge may be interpreted by the controller as anindication that the key or location on the touchpad was actuated. Thus,in an embodiment, the actuation by a user results in the controllersending a haptic feedback control signal back to the piezoelectricelement under the key or one or more of an array of piezoelectricelements under where the touchpad has been actuated. When the activatingelectrical haptic feedback control signal (with particular polarity,current, or voltage) is received at the piezoelectric element, thepiezoelectric material in the piezoelectric element may stretch orcompress to warp the piezoelectric element thereby creating the hapticfeedback at that key or location on the touchpad described herein.

Turning now to the figures, FIG. 1 illustrates an information handlingsystem 100 similar to information handling systems according to severalaspects of the present disclosure. In the embodiments described herein,an information handling system includes any instrumentality or aggregateof instrumentalities operable to compute, classify, process, transmit,receive, retrieve, originate, switch, store, display, manifest, detect,record, reproduce, handle, or use any form of information, intelligence,or data for business, scientific, control, entertainment, or otherpurposes. For example, an information handling system 100 may be apersonal computer, mobile device (e.g., personal digital assistant (PDA)or smart phone), server (e.g., blade server or rack server), a consumerelectronic device, a network server or storage device, a network router,switch, or bridge, wireless router, or other network communicationdevice, a network connected device (cellular telephone, tablet device,etc.), IoT computing device, wearable computing device, a set-top box(STB), a mobile information handling system, a palmtop computer, alaptop computer, a desktop computer, a communications device, an accesspoint (AP), a base station transceiver, a wireless telephone, a controlsystem, a camera, a scanner, a printer, a pager, a personal trusteddevice, a web appliance, or any other suitable machine capable ofexecuting a set of instructions (sequential or otherwise) that specifyactions to be taken by that machine, and may vary in size, shape,performance, price, and functionality.

In a networked deployment, the information handling system 100 mayoperate in the capacity of a server or as a client computer in aserver-client network environment, or as a peer computer system in apeer-to-peer (or distributed) network environment. In a particularembodiment, the information handling system 100 may be implemented usingelectronic devices that provide voice, video or data communication. Forexample, an information handling system 100 may be any mobile or othercomputing device capable of executing a set of instructions (sequentialor otherwise) that specify actions to be taken by that machine. Further,while a single information handling system 100 is illustrated, the term“system” shall also be taken to include any collection of systems orsub-systems that individually or jointly execute a set, or multiplesets, of instructions to perform one or more computer functions.

The information handling system may include memory (volatile (e.g.random-access memory, etc.), nonvolatile (read-only memory, flash memoryetc.) or any combination thereof), one or more processing resources,such as a central processing unit (CPU), a graphics processing unit(GPU), hardware or software control logic, or any combination thereof.Additional components of the information handling system 100 may includeone or more storage devices, one or more communications ports forcommunicating with external devices, as well as, various input andoutput (I/O) devices 112, such as a keyboard 114, a touchpad 113, amouse, a video/graphic display 110, or any combination thereof. Theinformation handling system 100 may also include one or more busesoperable to transmit communications between the various hardwarecomponents. Portions of an information handling system 100 maythemselves be considered information handling systems 100.

Information handling system 100 may include devices or modules thatembody one or more of the devices or execute instructions for the one ormore systems and modules described herein, and operates to perform oneor more of the methods described herein. The information handling system100 may execute code instructions 124 that may operate on servers orsystems, remote data centers, or on-box in individual client informationhandling systems according to various embodiments herein. In someembodiments, it is understood any or all portions of code instructions124 may operate on a plurality of information handling systems 100.

The information handling system 100 may include a processor 102 such asa central processing unit (CPU), control logic or some combination ofthe same. Any of the processing resources may operate to execute codethat is either firmware or software code. Moreover, the informationhandling system 100 may include memory such as main memory 104, staticmemory 106, or other memory of computer readable medium 122 storinginstructions 124 of the haptic feedback keyboard and touchpad controlsystem 132, and drive unit 116 (volatile (e.g. random-access memory,etc.), nonvolatile memory (read-only memory, flash memory etc.) or anycombination thereof. It is to be appreciated that the haptic feedbackkeyboard and touchpad control system 132 may be either a haptic feedbackkeyboard control system 132 for only a haptic keyboard or a hapticfeedback touchpad control system 132 for only a haptic touchpad 113 invarious embodiment herein. In particular, the haptic feedback keyboardand touchpad control system 132 may be separate system for controllingjust a haptic keyboard according to embodiments herein, or forcontrolling just a haptic touchpad 113 according to embodiments herein,or for controlling both. The haptic keyboard 114 and the haptic touchpad113 may have separate controllers or processors or share a controller ora processor according to embodiments herein. It is understood thatreference to the haptic feedback keyboard and touchpad control system132 does not necessarily require one system control both the haptickeyboard and the haptic touchpad 113 in embodiments herein. Someportions of the haptic feedback keyboard and touchpad control system 132may operate to enable the extended action haptic keys or extended actionhaptic touchpad 113 of the various embodiments described herein. Theinformation handling system 100 may also include one or more buses 108operable to transmit communications between the various hardwarecomponents such as any combination of various input and output (I/O)devices. For example, the haptic feedback keyboard and touchpad controlsystem 132 may execute code instructions via one or more keyboardcontrollers, touchpad controller, other controllers, or the processor102 to implement embodiments herein and further be operably coupled viabus 108 to the display screen of video display 110, the processor 102executing drivers for various components, or portions of the hapticfeedback keyboard and touchpad control system 132 that may operate ondistinct controllers or processors in such embodiments.

The information handling system 100 may include the video display 110.The video display 110 in an embodiment may function as a liquid crystaldisplay (LCD), an organic light emitting diode (OLED), a flat paneldisplay, or a solid-state display. Additionally, the informationhandling system 100 may include an input device 112, such as a cursorcontrol device (e.g., mouse, touchpad 113, or gesture or touch screeninput), and a keyboard 114. Various drivers and control electronics maybe operatively coupled to operate input devices 112 such as the haptickeyboard 114 and haptic touchpad 113 according to the embodimentsdescribed herein.

The network interface device shown as wireless adapter 120 may provideconnectivity to a network 128, e.g., a wide area network (WAN), a localarea network (LAN), wireless local area network (WLAN), a wirelesspersonal area network (WPAN), a wireless wide area network (WWAN), orother network. Connectivity may be via wired or wireless connection. Thewireless adapter 120 may operate in accordance with any wireless datacommunication standards. To communicate with a wireless local areanetwork, standards including IEEE 802.11 WLAN standards, IEEE 802.15WPAN standards, WWAN such as 3GPP or 3GPP2, or similar wirelessstandards may be used. In some aspects of the present disclosure, onewireless adapter 120 may operate two or more wireless links.

Wireless adapter 120 may connect to any combination of macro-cellularwireless connections including 2G, 2.5G, 3G, 4G, 5G or the like from oneor more service providers. Utilization of radiofrequency communicationbands according to several example embodiments of the present disclosuremay include bands used with the WLAN standards and WWAN standards, whichmay operate in both licensed and unlicensed spectrums. For example, bothWLAN and WWAN may use the Unlicensed National Information Infrastructure(U-NII) band which typically operates in the ˜5 MHz frequency band suchas 802.11a/h/j/n/ac (e.g., center frequencies between 5.170-5.785 GHz).

In some embodiments, software, firmware, dedicated hardwareimplementations such as application specific integrated circuits,programmable logic arrays and other hardware devices may be constructedto implement one or more of some systems and methods described herein.Applications that may include the apparatus and systems of variousembodiments may broadly include a variety of electronic and computersystems. One or more embodiments described herein may implementfunctions using two or more specific interconnected hardware modules ordevices with related control and data signals that may be communicatedbetween and through the modules, or as portions of anapplication-specific integrated circuit. Accordingly, the present systemencompasses software, firmware, and hardware implementations.

In accordance with various embodiments of the present disclosure, themethods described herein may be implemented by firmware or softwareprograms executable by a controller or a processor system. Further, inan exemplary, non-limited embodiment, implementations may includedistributed processing, component/object distributed processing, andparallel processing. Alternatively, virtual computer system processingmay be constructed to implement one or more of the methods orfunctionalities as described herein.

The present disclosure contemplates a computer-readable medium thatincludes instructions, parameters, and profiles 124 or receives andexecutes instructions, parameters, and profiles 124 responsive to apropagated signal, so that a device connected to a network 128 maycommunicate voice, video or data over the network 128. Further, theinstructions 124 may be transmitted or received over the network 128 viathe network interface device or wireless adapter 120.

The information handling system 100 may include a set of instructions124 that may be executed to cause the computer system to perform any oneor more of the methods or computer-based functions disclosed herein. Forexample, instructions 124 may execute a haptic feedback keyboard andtouchpad control system 132, software agents, or other aspects orcomponents. Various software modules comprising application instructions124 may be coordinated by an operating system (OS), and/or via anapplication programming interface (API). An example operating system mayinclude Windows®, Android®, and other OS types. Example APIs may includeWin 32, Core Java API, or Android APIs.

The disk drive unit 116 and the haptic feedback keyboard and touchpadcontrol system 132 may include a computer-readable medium 122 in whichone or more sets of instructions 124 such as software may be embedded.Similarly, main memory 104 and static memory 106 may also contain acomputer-readable medium for storage of one or more sets ofinstructions, parameters, or profiles 124 including haptic feedbackmodulation instructions that allow for a user to input a desired levelof haptic feedback at a key or location on a touchpad 113. The diskdrive unit 116 and static memory 106 may also contain space for datastorage. Further, the instructions 124 may embody one or more of themethods or logic as described herein. For example, instructions relatingto the haptic feedback keyboard and touchpad control system 132 softwarealgorithms, processes, and/or methods may be stored here. In aparticular embodiment, the instructions, parameters, and profiles 124may reside completely, or at least partially, within the main memory104, the static memory 106, and/or within the disk drive 116 duringexecution by the processor 102 of information handling system 100.

Main memory 104 may contain computer-readable medium, such as RAM in anexample embodiment. An example of main memory 104 includes random accessmemory (RAM) such as static RAM (SRAM), dynamic RAM (DRAM), non-volatileRAM (NV-RAM), or the like, read only memory (ROM), another type ofmemory, or a combination thereof. Static memory 106 may containcomputer-readable medium (not shown), such as NOR or NAND flash memoryin some example embodiments. The haptic feedback keyboard and touchpadcontrol system 132 may be stored in static memory 106, or the drive unit116 on a computer-readable medium 122 such as a flash memory or magneticdisk in an example embodiment. While the computer-readable medium isshown to be a single medium, the term “computer-readable medium”includes a single medium or multiple media, such as a centralized ordistributed database, and/or associated caches and servers that storeone or more sets of instructions. The term “computer-readable medium”shall also include any medium that is capable of storing, encoding, orcarrying a set of instructions for execution by a processor or thatcause a computer system to perform any one or more of the methods oroperations disclosed herein.

In a particular non-limiting, exemplary embodiment, thecomputer-readable medium may include a solid-state memory such as amemory card or other package that houses one or more non-volatileread-only memories. Further, the computer-readable medium may be arandom-access memory or other volatile re-writable memory. Additionally,the computer-readable medium may include a magneto-optical or opticalmedium, such as a disk or tapes or other storage device to storeinformation received via carrier wave signals such as a signalcommunicated over a transmission medium. Furthermore, a computerreadable medium may store information received from distributed networkresources such as from a cloud-based environment. A digital fileattachment to an e-mail or other self-contained information archive orset of archives may be considered a distribution medium that isequivalent to a tangible storage medium. Accordingly, the disclosure isconsidered to include any one or more of a computer-readable medium or adistribution medium and other equivalents and successor media, in whichdata or instructions may be stored.

The information handling system 100 may also include the haptic feedbackkeyboard and touchpad control system 132 that may be operably connectedto the bus 108. The haptic feedback keyboard and touchpad control system132 computer readable medium 122 may also contain space for datastorage. The haptic feedback keyboard and touchpad control system 132may, according to the present description, perform tasks related toreceiving an electric charge as an actuation signal from a piezoelectricelement and return a haptic feedback control signal to thatpiezoelectric element causing a haptic feedback at a key or location ona touchpad 113 associated with that piezoelectric element. In theseembodiments, the haptic feedback keyboard and touchpad control system132 may receive the electric charge from any of a plurality ofpiezoelectric elements each associated with a key on keyboard (i.e., aQWERTY keyboard), a keypad, or a location on a touchpad 113. Theelectrical charge actuation signal may vary in magnitude of charge levelwhich may correspond to the amount of mechanical stress applied to thepiezoelectric element causing a varied amount of deformation of thepiezoelectric element. This may correspond to a “depth” of the keypressor touchpad press based on the actuation force applied. The electriccharge actuation signal level may be detected as reaching one or morethreshold ranges that may each correspond to one or a plurality ofmulti-level functions or plurality of alphanumeric characters availableat an extended action key of keyboard 114 or extended action touchpad113. The haptic feedback keyboard and touchpad control system 132 maydetermine the threshold ranges met by the actuation signal and registera function or alphanumeric character depending on the threshold rangedetected according to embodiments herein. Further, the haptic feedbackkeyboard and touchpad control system 132 may assign one or more types ofhaptic feedback via a response haptic feedback control signal todistinguish the level of function selected or alphanumeric characterselected by the applied force to the extended action key of keyboard 114or extended action touchpad 113 in some embodiments herein. Further,visual feedback of the selection may be viewed via display screen 110 insome embodiments. Input may be received by the haptic feedback keyboardand touchpad control system 132 either simultaneously or concurrently soas to provide a return haptic feedback control signal to thecorresponding piezoelectric elements as described herein. The hapticfeedback keyboard and touchpad control system 132, in embodimentsherein, may be a control system for either a haptic feedback keyboard114 or for a haptic feedback touchpad system 113, or for both as shownin FIG. 1. For example, haptic feedback keyboard and touchpad controlsystem 132 may include only a keyboard controller 130 for a haptickeyboard system or only a touchpad controller 131 for a haptic touchpadsystem in some embodiments that do not implement a haptic system forboth the keyboard and touchpad. In other embodiments, both the keyboardcontroller 130 and touchpad controller 131 may be implemented for hapticinput output systems as described herein.

In an embodiment, the haptic feedback keyboard and touchpad controlsystem 132 may communicate with the main memory 104, the processor 102,the video display 110, the alphanumeric input device 112, and thenetwork interface device 120 via bus 108, and several forms ofcommunication may be used, including ACPI, SMBus, a 24 MHZ BFSK-codedtransmission channel, or shared memory. Keyboard driver software,firmware, controllers and the like may communicate with applications onthe information handling system 100.

In other embodiments, dedicated hardware implementations such asapplication specific integrated circuits, programmable logic arrays andother hardware devices may be constructed to implement one or more ofthe methods described herein. Applications that may include theapparatus and systems of various embodiments may broadly include avariety of electronic and computer systems. One or more embodimentsdescribed herein may implement functions using two or more specificinterconnected hardware modules or devices with related control and datasignals that may be communicated between and through the modules, or asportions of an application-specific integrated circuit. Accordingly, thepresent system encompasses software, firmware, and hardwareimplementations.

When referred to as a “system”, a “device,” a “module,” a “controller,”or the like, the embodiments described herein may be configured ashardware. For example, a portion of an information handling systemdevice may be hardware such as, for example, an integrated circuit (suchas an Application Specific Integrated Circuit (ASIC), a FieldProgrammable Gate Array (FPGA), a structured ASIC, or a device embeddedon a larger chip), a card (such as a Peripheral Component Interface(PCI) card, a PCI-express card, a Personal Computer Memory CardInternational Association (PCMCIA) card, or other such expansion card),or a system (such as a motherboard, a system-on-a-chip (SoC), or astand-alone device). The system, device, controller, or module mayinclude software, including firmware embedded at a device, such as anIntel® Core class processor, ARM® brand processors, Qualcomm® Snapdragonprocessors, or other processors and chipsets, or other such device, orsoftware capable of operating a relevant environment of the informationhandling system. The system, device, controller, or module may alsoinclude a combination of the foregoing examples of hardware or software.In an embodiment an information handling system 100 may include anintegrated circuit or a board-level product having portions thereof thatmay also be any combination of hardware and software. Devices, modules,resources, controllers, or programs that are in communication with oneanother need not be in continuous communication with each other, unlessexpressly specified otherwise. In addition, devices, modules, resources,controllers, or programs that are in communication with one another maycommunicate directly or indirectly through one or more intermediaries.

FIG. 2 is a perspective graphical diagram of an information handlingsystem 200 with a haptic feedback keyboard and touchpad control system132 according to an embodiment of the present disclosure. Although FIG.2 depicts the information handling system 200 as being implemented in alaptop computing device, FIG. 2 is not meant to be limiting and thepresent specification contemplates that the use of other types ofinformation handling system as described herein. In the example, theinformation handling system may include a screen portion 210 and akeyboard portion 201 and touchpad portion 202. The screen portion 210may include any device that may present to a user any visual data asoutput to a user in response to input and execution of the instructions,parameters, and profiles 124 by the processor 102 described inconnection with FIG. 1. In an example embodiment, a graphical userinterface may be presented to a user to input any number of parametersdescriptive of the actuation force used to actuate any number of keys220 including extended action keys on the keyboard portion 201 of theinformation handling system, an actuation force at a location on anextended action touchpad 202, or both. The graphical user interface(GUI) may also be used to receive other settings including actuation ofa “click” when selecting items on display 210 via a cursor usingtouchpad 202, setting the force required for actuation, settingmultiple-levels of force and operations associated with those levels,and selection of magnitude, pattern, or other characteristics of thehaptic response by a key 220 or touchpad 202 of the keyboard 201.

The keyboard portion 201 may include any number of keys 220, such asextended action keys, arranged in any manner so as to receive input froma user via selective actuation of those keys 220 including varyinglevels of applied force to select among levels of functions oralphanumeric characters associated with extended action keys 220. In anembodiment, the keys 220 may be arranged similar to a QWERTY-typekeyboard layout or any other alphabetic, symbolic, or numeric layout. Inembodiments herein as described further with respect to FIG. 10, one ormore extended action keys may be used to streamline the number or layoutof keys 220. In such embodiments, an optimized keyboard layout may beutilized to increase available space on a C-cover for a touchpad 202 orprovide for smaller information handling systems to have fuller functionkeyboards. In an embodiment, the keys 220 may be any number of keys from1 to infinity.

In an embodiment of the present description, each of the keys 220 may beassociated with a piezoelectric element. The piezoelectric element maybe used to, as described herein, create an electrical charge relative toa key 220 on the keyboard portion 215 and send that electrical charge toa controller. As described, the piezoelectric elements may be capable ofdetected several levels of applied force and send those levels aselectric charge actuation signals to a keyboard controller. In anembodiment, the controller may receive the electrical actuation signaland send one or more types haptic feedback control signals to thepiezoelectric element. Upon application of the haptic feedback controlsignal at the piezoelectric element (i.e., having a specific current andvoltage) associated with the actuated key 220 causes the piezoelectricelement to convert that haptic feedback control signal into a mechanicalstress by, for example, warping the piezoelectric element to generateone or more types of haptic feedback to the user including soundfeedback in some embodiments. The types of haptic feedback provided to apiezoelectric element may correspond to the level of force applied andselection from among a plurality of functions or characters associatedwith an actuated extended action key 220 or actuated location onextended action touchpad 202. The mechanical stress of the piezoelectricelement due to the application of the electrical charge to thepiezoelectric element may be felt by a user who actuated the key 220 orlocation on the touchpad 202.

In an embodiment, the touchpad portion 202 includes a touch surface anda capacitive touch layer that indicates a touch location using x- andy-coordinates across the touch surface. In an embodiment, an array ofpiezoelectric elements may be placed under the touch surface. Each ofthe piezoelectric elements among the array may detect and respond byproviding haptic feedback depending on the piezoelectric elements'proximity to an actuation location across the surface of the touchlayer. The array of piezoelectric elements activates the touch surfaceand is a detect/response by one or more nearby piezoelectric elements.The piezoelectric elements create a “click” haptic feedback such as whena user selects an item displayed with the haptic touchpad 202.

The information handling system 200 may include a haptic feedbackkeyboard and touchpad control system 132 as described herein. In anembodiment the keyboard controller 130 and the touchpad controller 131may be the same controller that executes instructions, parameter, andprofiles 124 to enact the functions of the keyboard 114 and touchpad asdescribed herein. In an embodiment the keyboard controller 130 and thetouchpad controller 131 may be the different controllers that eachexecutes instructions, parameter, and profiles 124 to enact thefunctions of the keyboard 201 and touchpad 202 as described herein. Inan embodiment, the haptic feedback keyboard and touchpad control system132 may include one or more sets of instructions that, when executed bya keyboard controller 130, causes one or more types haptic feedbackcontrol signals of varying voltage and polarity levels to be applied toa piezoelectric element upon detection of one or more threshold levelsof electrical charge actuation signals from the piezoelectric element.The one or more sets of instructions of the haptic feedback keyboard andtouchpad control system 132 may also include one or more sets ofinstructions that, when executed by the keyboard controller 130,determines which of any plurality of keys 220 on a keyboard portion 201or locations on a touchpad 202 were activated. The present embodimentscontemplate that only a haptic feedback keyboard 201 or only a hapticfeedback touchpad 202 may be deployed into the information handlingsystem with the other of the haptic feedback keyboard 201 or hapticfeedback touchpad 202 being embodied as a conventional touchpad orkeyboard. In an example, the keyboard controller 130 may receive, from apiezoelectric element, an electric charge and produce an electric chargeto the piezoelectric element. The haptic feedback and touchpad controlsystem 132 may also include a touchpad controller 131. In an embodiment,the touchpad controller 131 of the control system 132 may include one ormore sets of instructions that, when executed by a touchpad controller131, causes a current, at a voltage, to be applied to a piezoelectricelement upon detection of an electrical charge from the piezoelectricelement.

In an embodiment, the one or more sets of instructions of the hapticfeedback keyboard and touchpad control system 132 may also include, inan embodiment, one or more sets of instructions that, when executed by aprocessor, adjusts the polarity, voltage, or current of haptic responsesignals applied to any piezoelectric element. This adjustment may becompleted based on the desired haptic responses from the piezoelectricelements, the lifespan of the piezoelectric element, the electricalcharacteristics of the piezoelectric element, the mechanicalcharacteristics of the piezoelectric element, or combinations thereof.Because these characteristics may be different from one piezoelectricelement to the other, the electrical charge applied any givenpiezoelectric element by the keyboard controller 130 may be customizedto produce a specific level of haptic feedback at any given key. In anembodiment, the keyboard controller 130 of the information handlingsystem 200 may include a look-up table. In various embodiments, thekeyboard controller 130 of the information handling system 200 mayaccess the look-up table in order to determine how a current pulse is tobe applied to any given piezoelectric element and at what polarity orvoltage of the haptic response signal to the piezoelectric elementsdepending on user selection or depending on the received threshold levelof electric charge actuation signal. For example, the received thresholdlevel of electrical charge actuation signal may indicate via a look uptable the corresponding function or character selected based on theapplied “depth” or actuation force applied to the piezoelectric elementas well as the look-up table may have differing functions and charactersdepending on which extended action key or location on extended actiontouchpad is actuated in various embodiments. Moreover, a lookup tablemay further associate the threshold of force applied to a correspondingtype of haptic feedback or haptic feedback control signal in otherembodiments.

The one or more sets of instructions of the haptic feedback keyboard andtouchpad control system 132 may also include one or more sets ofinstructions that, when executed by the keyboard controller 130, causesany number of subsequent current pulses to be applied to anypiezoelectric element. In this embodiment, the subsequent electricalpulses may cause a haptic feedback event to a user who actuated a key220 on a keyboard portion 201 of the information handling system orchanges in magnitude or pulses of haptic feedback to emulate the feel ofa mechanical keystroke including adjustment of the feel of depth of thehaptic-emulated keystroke. In other embodiments, the haptic feedback ofthe keyboard 201 may not need to emulate a keystroke of a mechanicallyactuated keyboard but instead provide a distinct haptic feel to indicatethat a keystroke has occurred on the solid state keyboard 201 to theuser.

In an embodiment, the one or more sets of instructions of the hapticfeedback keyboard and touchpad control system 132 may also include, inan embodiment, one or more sets of instructions that, when executed by aprocessor, adjusts the voltage and current applied to any piezoelectricelement at a touchpad portion 202. This adjustment may be completedbased on the desired haptic responses from the piezoelectric elements,the lifespan of the piezoelectric element, the electricalcharacteristics of the piezoelectric element, the mechanicalcharacteristics of the piezoelectric element, or combinations thereof.Because these characteristics may be different from one piezoelectricelement to the other, the electrical charge applied any givenpiezoelectric element by the touchpad controller 131 may be customizedto produce a specific level of haptic feedback at any given locationacross the touchpad. In an embodiment, the touchpad controller 131 ofthe information handling system 200 may include a look-up table. In thisembodiment, the touchpad controller 131 of the information handlingsystem 200 may access the look-up table in order to determine how acurrent pulse is to be applied to any given piezoelectric element and atwhat polarity or voltage of the haptic response signal to thepiezoelectric elements.

The one or more sets of instructions of the haptic feedback keyboard andtouchpad control system 132 may also include one or more sets ofinstructions that, when executed by the touchpad controller 131, causesany number of subsequent current pulses to be applied to anypiezoelectric element. In this embodiment, the subsequent electricalpulses may cause a haptic feedback event to a user who actuated alocation across a touchpad portion 202 of the information handlingsystem or changes in magnitude or pulses of haptic feedback to emulatethe feel of a mechanical actuation of a touchpad portion 202 includingadjustment of the feel of depth or click response of the haptic-emulatedactuation of the touchpad portion 202. In other embodiments, the hapticfeedback of the touchpad 202 may not need to emulate a click of amechanically actuated touchpad but instead provide a distinct hapticfeel to indicate that a touchpad selection has occurred on the solidstate touchpad 202 to the user.

In an embodiment, the application of any current and voltage applied toany of the piezoelectric elements associated with any of the keys 220 ora location on a touchpad portion 202 may be dependent on an applicationbeing executed on the laptop computing device 205. By way of example, auser may be engaged in providing input, via the keys 220 of the keyboardportion 215, to a processor of the laptop computing device 205 in orderto cause output to be provided. In a specific embodiment, the laptopcomputing device 205 may execute a basic input/output system (BIOS).Upon execution of the BIOS, the haptic feedback keyboard and touchpadcontrol system 132 may begin to detect electrical signals or chargesemitted from a piezoelectric element being placed in a strain by theactuation of a corresponding key 220 on the keyboard portion 215 orlocation on a touchpad portion 202. This may allow the haptic feedbackkeyboard and touchpad control system 132 to receive input at times whenthe laptop computing device 205 is in an on states. In an alternativeembodiment, the execution of other application programs by a processorof the laptop computing device 205 such as word processing applicationprogram may trigger the haptic feedback keyboard and touchpad controlsystem 132 to begin to detect the electrical charges produced at anygiven piezoelectric element. By deferring input received from thepiezoelectric element at the keyboard controller 130 or any othercontroller or processor, accidental input may be prevented by any erranttouch of the keyboard portion 215.

FIG. 3A is a side cut-out view of a key 300 of a keyboard implementing apiezoelectric element 320 in an unactuated state according to anembodiment of the present disclosure. According to an embodiment, thekey 300 may be formed of a plurality of layers, one layer of which is apiezoelectric element 320. Although FIG. 3A shows a cross-sectional viewof a single key 300, the present specification contemplates that akeyboard may also include a plurality of these similar keys 300 arrangedas, for example, a QWERTY-type keyboard. The present specification alsocontemplates that, in addition to a keyboard, an information handlingsystem described herein may also include a touchpad including apiezoelectric element 320 as described herein. Consequently, FIG. 3A isnot intended to be limiting but merely intended as a description ofoperation of any type of input device contemplated by the presentdisclosure.

The key 300 includes a coversheet 305. The coversheet 305 may be made ofany type of elastically resilient material. The elastically resilientmaterial may allow, at least, a portion of the key 300 to be deformedupon application of a pressure from a user's finger. Upon withdraw ofthe pressure from the user's finger, the material the coversheet 305 ismade of allows the coversheet 305 of the key 300 to bend back to itspre-deformed state. In an embodiment, the resilient material may allowthe coversheet 305 to travel a minimal distance and still deform apiezoelectric element 320. For example, a distance of between 0.01 mmand 2 mm may be compressed in the stackup including the coversheet 305and piezoelectric element. In an embodiment, the distance is between0.05 mm and 0.15 mm. In an embodiment, the distance is 0.1 mm. Thepiezoelectric element 320 may deform between 5 microns and 30 microns insome embodiments. Varying levels of piezoelectric element deformationmay be detected as levels of accumulated electrical charge since furtherdeformation of piezoelectric element 320 may correspond to a higherlevel of mechanical stress from greater applied force according toembodiments herein.

In an embodiment, the shape of the coversheet 305 may have a selectionof key pedestals 306 of various sizes and shaped so as to conform to auser's finger. In an embodiment, in order to shape the coversheet 305,the material used to form the coversheet 305 may be subjected to aninjection molding process. As such, a top portion of the coversheet 305may be formed to be ergonomically beneficial to a user's actuation suchas by conforming to the user's fingers and including a pedestal 306 tohighlight the key location, for example. In other embodiments, no keypedestals may be formed and a key location may be described incoversheet 305 via markings, depressions, key framing, or other methods.The injection molding process may be completed prior to the installationof the coversheet 305 into the remaining layers within the keyboard 300as described herein. Any number of processes may be included with theinjection molding process. In an embodiment, the injection moldingprocess used to form the coversheet 305 may include forming a number ofholes within a sheet of acrylonitrile butadiene styrene (ABS). Theseholes may correlate with a number of keys on a keyboard. The formationof the coversheet 305 may continue with injection molding a translucentABS through the holes to form a raised portion correlating with each ofthe number of keys on the keyboard. Opposite the raised portions anumber of runners may be machined away to accommodate for receipt ofother layers of the keyboard such as each of the piezoelectric elements.The surface of the coversheet on which the raised portions are formedmay be painted and any number or type of graphics may be laser etched oneach raised portion indicating a specific key of the keyboard.

In yet other embodiments, coversheet of the C-cover may include aplurality of vias for keys 300 having a cover sheet 305 or cap for eachkey. A key pedestal 306 for each key 300 in a solid state keyboard ofthe present embodiments may be disposed through the vias in the C-coverin such embodiments. Keys 300 may include small gaps that may beavailable for base chassis ventilation, or for allowing backlightframing of keys in some embodiments. Similarly, in some embodiments avia for touchpad interface surface may be provided in a C-covercoversheet for access to the top cover sheet of the solid state touchpadin some embodiments.

The key 300 may further include a number of adhesive layers 315 thatphysically couple the various layers of the key 300 together. In anembodiment, a first adhesive layer 315 may be formed on the coversheet305 to adhere the coversheet 305 to a contact foil 310. The firstadhesive layer 315 may include the placement of the adhesive atlocations that may enhance the movement and prevent the hinderance ofthe actuation of the coversheet 305. In a specific embodiment, the firstadhesive layer 315 may include placing the adhesive along borders of thekey 300 as well as placing the adhesive at a central location of the key300.

The contact foil 310 adhered to the coversheet 305 via the first layerof adhesive 315 may be made of any elastically resilient material that,when the coversheet 305 of key 300 is actuated or the contact foil 310is bent towards a lower portion of the key 300, returns to its originalstate when the key 300 is no longer being actuated. The contact foil isa flexible material, such as polyethylene terephthalate (PET) serving asa polyester printed circuit board or other type of flexible printedcircuit board, in several example embodiments. The contact foil 310 mayinclude a number of metal traces formed thereon that electrically andcommunicatively couple each of the corresponding piezoelectric element320 of key 300 to a controller such as a processor of an informationhandling system that includes a haptic feedback keyboard control systemsuch as described herein. Formation of metal traces may be madeaccording to a variety of methods including photolithographic techniquesfor applying metal or lamination of copper strips or other metal layers.During operation of the key 300, the contact foil 310 may receive anelectrical charge from the piezoelectric element 320 at the metal tracesthat conduct the electrical charge to the processor or other controllerassociated with the key 300. The metal traces formed on the contact foil310 may further be used to conduct a return haptic feedback controlsignal from the controller to the piezoelectric element 320 so that thevoltage and current of the return haptic feedback control signal maycause the piezoelectric element 320 to return to a planer and rigidpiezoelectric element 320 as required to cause a specified hapticresponse to the user via coversheet 305. This stiffening of thepiezoelectric element 320 may cause a haptic feedback presented at thekey 300 via the contact foil 310, adhesive 315, and coversheet 305 thatthe user may feel. This haptic feedback may be relayed to the userwithin microseconds of the user actuating the key 300 such that the userphysically detects a sensation that the key 300 was pressed. Thissensation felt by the user may be present despite no actual mechanicaldevices such as a scissor mechanism or other types of keyboardmechanical devices being present among the layers of the key 300. Thesignal to the piezoelectric element 320 may vary magnitude and pulsingto create the desired haptic response at key 300.

In an embodiment, portions of the contact foil 310 may be physicallycoupled to a support plate 330 via a second layer of adhesive 316. Thelocation of the placement of the second adhesive layer 316 may includeplacing the adhesive along borders of the key 300.

In an embodiment presented herein, the piezoelectric element 320 mayinclude a first portion 322 that may be any solid piezoelectric materialthat accumulates an electric charge when a mechanical stress is appliedto it or specifically, in the embodiments presented herein, when thesolid material is deformed. Solid materials used to form thepiezoelectric element 320 may include crystals, ceramics, or proteinlayers, among other types of materials. For ease of explanation, thepiezoelectric element 320 may be made of a type of ceramic although thepresent specification contemplates the use of other types ofpiezoelectric materials.

The piezoelectric element 320 may be housed over a cavity 331 formed inthe support plate 330. The piezoelectric element 320 may comprise twoportions 322 and 325 each electrically coupled via electric contactpoints such as soldering points 335 and 340, respectively, to adifferent electrical trace on a contact foil 310. The first portion 322may be a ceramic disc in an embodiment. Second portion 325 of thepiezoelectric element 320 may be a metal plate or ring, such as a brassplate, that extends beyond the edges of cavity 331. The first portion322 and the second portion 325 may be operatively coupled via adhesiveincluding conductive adhesives. The soldering points 335 and 340 may besilver solder contact points for operative electrical coupling to metaltraces on contact foil 310. The brass plate 325 supports deflection ofthe piezoelectric element 320 into the cavity 331 to detect mechanicalactuation of the key 300. In an embodiment, the support plate 330 mayhave cavity 330 formed therein such that the piezoelectric element 320may be allowed to be deflected therein when the key 300 is actuated by auser and cavity 331 may be an aperture or hole through support plate 330or may be a depression or hole in support plate 330 that does not passthrough 330.

The piezoelectric element 320 may be electrically and communicativelycoupled to the metal traces formed on the contact foil 310 via ametallic connection points 335 and 340 such as a solder dot. In aspecific embodiment, the piezoelectric element 320 may be electricallyand communicatively coupled at a first portion 322 to a metallic traceformed on the contact foil 310 by a first soldering point 335 and at asecond portion 325 to a metallic trace in contact foil 310 via a secondsoldering point 340. The soldering points 335 and 340 may be silvercontact points for making electrical contact to first portion 322 andsecond portion 325 of the piezoelectric element 320. As so oriented, thefirst soldering point 335 and second soldering point 340 may be formedto receive an electrical charge upon deflection of the piezoelectricelement 320 as a user actuates the key 300. As described herein, theelectrical charge may be detected by the controller as received from theelectrically-conductive metal traces and portions 322 and 325.

Upon receiving an actuation signal, the controller sends a hapticfeedback control signal back to the piezoelectric element 320 via themetal traces formed on the contact foil 310, through the solderingpoints 335 and 340 and to a conductive layer of metallic plate or ring325 formed below the piezoelectric disk material 322. The conductivelayer of metallic plate or ring 325 may apply the haptic feedbackcontrol signal to the piezoelectric disk material 322 so as to cause thepiezoelectric disk material 322 to stretch or shrink depending on thepolarity of the signal applied. For example, a negative signal appliedto piezoelectric disk material element 322 relative to the charge atadhesively attached metallic plate 325 may cause piezoelectric disk 322to expand or stretch in embodiments herein. This may cause metallicplate 325 to warp downward. Reversing polarity to the piezoelectric disk322 may cause the piezoelectric disk 322 to compress or shrink andmetallic plate 325 may warp upwards. The principle of haptics applied tothe piezoelectric disk 322 includes an input voltage is applied throughthe two electrodes (voltage change as sine wave, square wave etc.) togenerate movement on piezoelectric material 322 of the piezoelectricelement 320 and a warping of the metallic layer or disk 325. This hapticresponse signal is used to cause a haptic tactile feedback such as adepression and return of the key 300 or a haptic “click” of a touchpadand which may be accompanied by a sound. Such a haptic feedback controlsignal, such as a sine wave signal, or other haptic response signalswith varying polarities or voltage and current may be used by thecontroller to create the haptic feedback felt by the user as describedherein. In these embodiments, the electric charge sent from thepiezoelectric element 320 to the controller and the haptic feedbackcontrol signal sent from the controller to the piezoelectric element 320may propagate along the two metal traces formed on the contact foil 310.The contact foil 310 may therefore, in an embodiment, include double thenumber of metal traces as that of the number of piezoelectric elements320 used to form a keyboard that includes multiple keys 300.

FIG. 3A shows an image of a single key 300. The present specificationcontemplates that a plurality of keys 300 may be formed alongside eachother in order to form, for example, a number pad, a keyboard, or acombination thereof. Consequently, although the features of the key 300depicted in FIG. 3A apply to a single key 300, the present specificationcontemplates that any number of keys 300 may be formed on the keyboardso as to allow for the formation of an input device such as a keyboard.The keys 300 may be of any size (e.g., spacebar, tab key, or the like)and depending on size may include more than one piezoelectric element320 associated with it. As the user actuates each of the keys 300, ahaptic feedback may be felt by the user so as to present to the user asensation that the key was pressed.

The formation of the key 300 may, in the embodiments presented herein,provides for a keyboard that has a relatively shorter distance of keytravel as compared to those keyboards that implement mechanical devicessuch as a scissor mechanisms and key caps. Further, as described inembodiments herein, levels of piezoelectric deformation may be detectedat the piezoelectric element to provide for an extended action key asseen in more detail below. In an embodiment, the distance of travel ofthe key 300 may be smaller than 0.1 mm. With the shorter distance of keytravel, the overall thickness of the keyboard placed within aninformation handling system may be reduced. This increases the availablefootprint within a base chassis of, for example, a notebook-typeinformation handling system that may be used for more or largercomponents (e.g., batteries) to be placed within the base chassis.Additionally, or alternatively, the reduction in thickness of thekeyboard may reduce the overall thickness of the information handlingsystem improving the aesthetics of the design of the informationhandling system. This reduction in size of the information handlingsystem may also result in the reduction of the weight of the informationhandling system thereby increasing the portability of the informationhandling system by the user.

The keys 300 of the present embodiments also include no movingmechanical parts. With the absence of mechanical moving parts, the key300 of the presently described embodiments may be relatively more robustthereby increasing the useful life of the key 300. This may increaseuser satisfaction over the useful lifetime of the information handlingsystem.

FIG. 3B is an enlarged side cut-out view of an extended action key 300of a keyboard implementing a piezoelectric element 320 in a firstactuated state by a finger 355 according to an embodiment of the presentdisclosure. This may be compared to FIG. 3C also showing an enlargedside cut-out view of an extended action key 300 of a keyboardimplementing a piezoelectric element 320 in a second actuated state by afinger 355 where additional mechanical deformation has been applied withgreater actuation force on the extended action key 300 according to anembodiment of the present disclosure. According to an embodiments ofFIG. 3B and FIG. 3C described herein, the extended action key 300 may beformed of a plurality of layers, one layer of which is a piezoelectricelement 320 made of a piezoelectric material, such as piezoelectric disk322, and a of metallic plate or ring 325. Although FIG. 3B and FIG. 3Cshow a cross-sectional view of a single extended action key 300, thepresent specification contemplates that a keyboard may include aplurality of these keys 300 with or without extended actionfunctionality. Also, a C-cover layer may further include a touchpadincluding a piezoelectric element 320 as described herein. Consequently,FIG. 3B and FIG. 3C are not intended to be limiting but merely intendedas a description of operation of any portion of the input devicecontemplated by the present disclosure.

The extended action key 300 includes a coversheet 305. The coversheet305 may be made of any type of elastically resilient material. Thecoversheet 305 may cover a plurality of keys but also be continuous andcover any touchpad on the C-cover in some embodiments described herein.In other embodiments, one or both of a keyboard or touchpad may beseparately disposed at vias in the coversheet of the C-cover asdescribed herein. The elastically resilient material may allow, atleast, a portion of the extended action key 300 to be deformed uponapplication of a pressure from a user's finger to multiple levels asshown in FIG. 3B and FIG. 3C. Upon withdraw of the pressure from theuser's finger, the material the coversheet 305 is made of allows thecoversheet 305 of the extended action key 300 to bend back to itspre-deformed form. In an embodiment, the resilient material may allowthe coversheet 305 to travel a distance of between 0.01 mm and 2 mm.FIG. 3B shows, in contrast to FIG. 3A, the deformation of the coversheet305 piezoelectric element 320, and conductive layer 325. The deformationis shown at 344 in FIG. 3B. FIG. 3C shows, in contrast to FIG. 3B, agreater level of deformation 345 of the coversheet 305 piezoelectricelement 320, and conductive layer 325 as compared to the deformationlevel 344 of FIG. 3B.

In some embodiments of FIG. 3B and FIG. 3C, portions of a first adhesivelayer 316 and second adhesive layer 315 placed between the remaininglayers of the key 300 may also be compressed when the finger 355 of auser deforms the remaining layers of the key 300.

In an embodiment, the shape of the coversheet 305 may include keypedestal 306 and may be concave so as to conform to a user's finger. Inan embodiment, in order to shape the coversheet 305, the material usedto form the coversheet 305 may be subjected to an injection moldingprocess. As described herein, this may include multiple keys of akeyboard as well as other portions of the C-cover including anypiezoelectric touchpads as described herein. A top portion of thecoversheet 305 may be formed to be ergonomically beneficial to a user'sactuation such as providing key or touchpad location identification suchas key pedestal or framing or by conforming to the user's fingers, forexample. The injection molding process may be completed prior to theinstallation of the coversheet 305 into the remaining layers within thekeyboard or touchpad as described herein. Any number of processes may beincluded with the injection molding process. In an embodiment, theinjection molding process used to form the coversheet 305 may includeforming a number of holes within a sheet of acrylonitrile butadienestyrene (ABS). These holes may correlate with a number of keys on akeyboard. The formation of the coversheet 305 may continue withinjection molding a translucent ABS through the holes to form a raisedportion as a key pedestal correlating with each of the number of keys onthe keyboard. Opposite the raised portions a number of runners may bemachined away to accommodate for receipt of other layers of the keyboardsuch as each of the piezoelectric elements. The surface of thecoversheet on which the raised portions are formed may be painted andany number or type of graphics may be laser etched on each raisedportion indicating a specific key of the keyboard.

In other embodiments, each extended action key 300 may be formed suchthat it has a coversheet 305 with key pedestals 306 disposed through keyvias in the C-cover coversheet (not shown). In such embodiments, theextended action key 300 shown in FIG. 3B and FIG. 3C may be a structurefor one or more keys of a solid state keyboard with any of the layersbeing independent or shared among the plurality of keys 300 in thekeyboard.

In other embodiments, the coversheet 305 may include number holes forkey vias and for a touchpad via. Each haptic key of the haptic keyboardmay include a cover layer that protrudes through the key vias in thecoversheet 305. Layering under the coversheet may include materiallayers that are hydrophobic or have other properties. Though gapsbetween haptic keys and key vias may be minimized, such gaps may beuseful for cooling ventilation of the base chassis or for allowingbacklighting to frame the haptic keys. Similarly, a touchpad top touchinterface layer may be attached under the coversheet 305 to seamlesslyprovide a designated touchpad area in the C-cover coversheet 305. Anycombination of continuous coversheet for haptic keys or the haptictouchpad and vias in the coversheet for placement of haptic keys of akeyboard or a touchpad top touch interface layer are contemplated invarious embodiments. Further, it is contemplated that in someembodiments one or the other of a haptic keyboard or haptic touchpad maybe used with a keyboard having mechanically actuated keys or a touchpadwith a mechanically actuate diving board mechanism.

The extended action key 300 of FIG. 3B and FIG. 3C may further include anumber of adhesive layers 315 such as the first adhesive layer 315 andsecond adhesive layer 316 described herein that physically couples thevarious layers of the key 300 together. In an embodiment, the firstadhesive layer 315 may be formed on the coversheet 305 to adhere thecoversheet 305 to a contact foil 310. The first adhesive layer 315 maybe include the placement of the adhesive at locations that may enhancethe movement or prevent the hinderance of the actuation of thecoversheet 305. In a specific embodiment, the first adhesive layer 315may include placing the adhesive along borders of the key 300 as well asplacing the adhesive at a central location of the key 300.

The contact foil 310 adhered to the coversheet 305 via the first layerof adhesive 315 may be made of any elastically resilient material that,when the key 300 is actuated by a user's finger 355 or the contact foil310 is bent towards a lower portion of the key 300, returns to itsoriginal state when the key 300 is no longer being actuated. The contactfoil 310 may include a number of metal traces formed thereon thatelectrically and communicatively couple each of the keys 300 and acorresponding piezoelectric element 320 to a controller such as aprocessor of an information handling system that includes a hapticfeedback keyboard control system such as described in connection withFIG. 1. During operation of the extended action key 300, the contactfoil 310 may receive an electrical charge at varying levels from thepiezoelectric element 320 at the metal traces that conduct theelectrical charge to the processor or other controller associated withthe key 300. As the piezoelectric disk material 322 is compressed bydeflection and the metal plate or ring 325 warped downward, a change involtage may be detected and may correspond to the amount of compressionapplied to 322 due to applied force on the extended action key 300. Theelectrical charge of varying levels is created when the user actuatesthe extended action key 300 with the user's finger 355 and thepiezoelectric element 320 is subjected to a mechanical stress may bedetected between soldering points 335 and 340. The electrical charge iscommunicated down metal traces formed on the contact foil 310 to acontroller (not shown) as an actuation signal. As described, one or morefunctions or characters may be selected via the extended action key 300of FIG. 3B and FIG. 3C depending on the level of deflection received atpiezo electric element 320.

The metal traces formed on the contact foil 310 may further be used toconduct one or more return haptic feedback control signals from thecontroller to the piezoelectric element 320 so that the voltage andcurrent of the return haptic feedback control signal may cause thepiezoelectric element 320 compress further and then contract to returnto a planer and rigid piezoelectric element 320 in one or more types ofhaptic feedback. This actuation of the piezoelectric element 320 maycause one or more types of haptic feedback presented at the extendedaction key 300 that the user may feel at the user's finger 355. Thishaptic feedback may be relayed to the user within microseconds of theuser actuating the extended action key 300 with the user's finger 355such that the user physically detects a sensation, at that finger 355,that the extended action key 300 was pressed. Further, the one or moretypes of haptic feedback presented at the extended action key 300 thatthe user may feel at the user's finger 355 may indicate the level ofdeflection applied and thus the function or character selected. Thissensation felt by the user may be present despite no actual mechanicaldevices such as a scissor mechanism of other types of keyboardmechanical devices being present among the layers of the extended actionkey 300.

In an embodiment, portions of the contact foil 310 may be physicallycoupled to a support plate 330 via a second layer of adhesive 316. Thelocation of the placement of the second adhesive layer 316 may includeplacing the adhesive along borders of the key 300.

In an embodiment presented herein, the piezoelectric element 320 may beany solid material that accumulates an electric charge when a mechanicalstress is applied to it or specifically, in the embodiments presentedherein, the solid material is deformed. Solid materials used to form thepiezoelectric disk 322 or other piezoelectric material as part of afirst portion 322 of the piezoelectric element 320 may include crystals,ceramics, biological matter, protein layers, among other types ofmaterials. For ease of explanation, the piezoelectric disk material 322may be made of a type of ceramic although the present specificationcontemplates the use of these other types of materials.

The piezoelectric element 320 may be housed over a cavity 331 formedunder a bottom surface of the contact foil 310. The cavity 331 may beformed into or through a top surface of the support plate 330, and thesecond layer of adhesive 315. In an embodiment, the support plate 330may have the cavity 331 formed therein such that the piezoelectricelement 320 may be allowed to be deflected therein when the extendedaction key 300 is actuated by application of one or more levels of forceof the user's finger 355.

The piezoelectric element 320 may be electrically and communicativelycoupled to the metal traces formed on the contact foil 310 via ametallic connection point such as a solder dot 335, 340. The solderingpoints 335 and 340 may be silver contact points for making electricalcontact to first portion 322 and second portion 325 of piezoelectricelement 320. In a specific embodiment, the piezoelectric element 320 maybe electrically and communicatively coupled to a metallic trace formedon the contact foil 310 by a first soldering point 335 and a secondsoldering point 340. The first portion 322 of piezoelectric element 320,such as a piezoelectric disk, may be coupled to the contact foil 310 viathe first soldering point 335. The second portion 325 of piezoelectricelement 320, such as a metal plate or ring, may be coupled to thecontact foil 310 via the second soldering point 340. As so oriented, thefirst soldering point 335 and second soldering point 340 may be formedto receive an electrical charge upon deflection and mechanical stress ofthe piezoelectric disk 322 as a user's finger 355 actuates the extendedaction key 300. As described herein, the electrical charge may bedetected by the controller as received from the electrically-conductivemetal traces and portions 322 and 325.

Upon receiving an actuation signal, the controller sends a hapticfeedback control signal back to the piezoelectric element 320 via themetal traces formed on the contact foil 310, through the solderingpoints 335 and 340 and to a conductive layer of metal plate or ring 325formed below the piezoelectric disk material 322. The conductive layerof metal plate or ring 325 and contact point 335 may apply one or morehaptic feedback control signals to the piezoelectric disk material 322so as to cause the piezoelectric disk material 322 to stretch or shrinkdepending on the polarity of the signal applied. For example, a negativesignal applied to piezoelectric disk material 322 relative to the chargeat adhesively attached metallic plate 325 may cause piezoelectric disk322 to contract or shrink in embodiments herein. This may cause metallicplate 325 to warp downward. Reversing polarity to the piezoelectric disk322 may cause the piezoelectric disk 322 to stretch and metallic plate325 may warp upwards. The principle of haptics involves an input voltageapplied through the two electrodes (with a responsive voltage changesignal such as a sine wave, a square wave, or other wave form thatchanges in polarity, voltage, or current) to generate movement onpiezoelectric material of the piezoelectric element 320 which causes ahaptic feedback event in coordination with warping the metallic plate325 based on the movement of the piezoelectric material layer 322. Atactile haptic sensation, such as a mimicked keystroke or “click,” maybe generated in some example embodiments of haptic feedback events andmultiple levels of “depth” or repeated clicks may indicate to a userthat an additional level of pressure has been reached and selection of anext level of function or character has occurred. The haptic feedbackevent may also be accompanied by a generated sound in some embodiments.Such an electrical haptic feedback signal, such as a sine wave signal,square wave signal, pulsed signals, or other signals varying polarities,voltages, or currents may be used by the controller to create the hapticfeedback felt by the user at the user's finger 355 as described herein.In these embodiments, the electric charge sent from the piezoelectricelement 320 to the controller and the haptic feedback control signalsent from the controller to the piezoelectric element 320 may propagatealong the two metal traces formed on the contact foil 310. The contactfoil 310 may therefore, in an embodiment, include double the number ofmetal traces as that of the number of piezoelectric elements 320 used toform a keyboard that includes multiple keys 300.

FIG. 3B and FIG. 3C show images of a single extended action key 300. Thepresent specification contemplates that a plurality of extended actionkeys 300 or haptic feedback keys such as 300 not implementing extendedaction which may be formed alongside each other in order to form, forexample, a number pad, a keyboard, or a combination thereof.Consequently, although the features of the extended action key 300depicted in FIG. 3B and FIG. 3C apply to a single extended action key300, the present specification contemplates that any number of keysextended action 300 may be formed on the keyboard so as to allow for theformation of an input device such as a keyboard. The extended actionkeys 300 may be of any size (e.g., spacebar or a tab key) and in someembodiments more than one piezoelectric element may be associated withlarger keys. As the user actuates each of the extended action keys 300,a haptic feedback may be felt by at the user's finger 355 so as topresent to the user a sensation that the key was pressed and at whatlevel a multi-level function or character option has been selected bythe actuation press.

The formation of the extended action key 300 may, in the embodimentspresented herein, provides for a keyboard that has a relatively shorterdistance of key travel, while still accommodating multiple forceapplication levels which may be perceived as differing “depths,” ascompared to those keyboards that implement mechanical devices such as ascissor mechanisms and key caps. In an embodiment, the distance oftravel of the extended action key 300 may be smaller than 0.1 mm. Withthe shorter distance of key travel, the overall thickness of thekeyboard placed within an information handling system may be reduced.This increases the available footprint within a base chassis of, forexample, a notebook-type information handling system that may be usedfor more or larger components (e.g., batteries) to be placed within thebase chassis. Additionally, or alternatively, the reduction in thicknessof the keyboard may reduce the overall thickness of the informationhandling system improving the aesthetics of the design of theinformation handling system. Moreover, with the use of extended actionkeys 300, a more optimized key layout of a haptic keyboard may beutilized to allow an even more streamline space usage in a base chassisas well over the surface of the C-cover of the base chassis.Additionally, the optimized key layout utilizing extended action keys300 may also permit more full function keyboards to be used with smallerinformation handling system. This reduction in size of the informationhandling system may result in the reduction of the weight of theinformation handling system thereby increasing the portability of theinformation handling system by the user.

FIG. 3D is a side cut-out view of a key 300 of a haptic feedbackkeyboard implementing a piezoelectric element in a downward warpedposition according to an embodiment of the present disclosure. Asdescribed herein, a haptic feedback control signal may be transmittedfrom the controller to the piezoelectric element to a piezoelectricelement of a haptic keyboard to cause a haptic movement or sound. Forexample, upon receiving a haptic actuation indicator signal indicating ahaptic tactile feedback movement or sound is needed, the controller (notshown) in an embodiment may send a haptic feedback control signal to thepiezoelectric element 320 via the metal traces formed on the contactfoil 310, through the soldering points 335 and 340 and to a conductivelayer of metallic plate or ring 325 formed below the piezoelectric diskmaterial 322. Such a haptic actuation indicator signal in an embodimentmay be one or more piezo actuation signal levels received at thecontroller or processor, indicating a key situated above thepiezoelectric element 320 has been actuated by a user at one or morelevels of applied force, as described in greater detail in embodimentsherein. In other embodiments, a haptic actuation indicator signal maycomprise a notification or code instructions received at the processoror controller from a software application currently operating on theinformation handling system. For example, some applications may includealarms or notifications that may be set to make an audible sound via thehaptic keyboard, rather than through the main speaker system of theinformation handling system. As another example, some applications maycause the haptic keyboard, in lieu of or in combination with the mainspeakers of the information handling system to emit sound in accordancewith an audio signal having one or more channels for one or morespeakers. Such notifications or audio signals in an embodiment maycomprise a haptic actuation indicator signal.

The conductive layer of metallic plate or ring 325 may apply the hapticfeedback control signal to the piezoelectric disk material 322 so as tocause the piezoelectric disk material 322 to stretch or shrink dependingon the polarity of the signal applied. For example, a negative voltagehaptic feedback control signal applied to piezoelectric disk materialelement 322 at soldering point 335 relative to a positive voltage hapticfeedback control signal applied at soldering point 340 may causepiezoelectric disk 322 to compress or shrink in embodiments herein. Thismay, in turn, cause the metallic layer or disk 325 adhered to theceramic piezoelectric disk 322 to warp downward as shown in FIG. 3D.Further in the example shown in FIG. 3E, a positive voltage hapticfeedback control signal applied to piezoelectric disk material element322 at soldering point 335 relative to a negative voltage hapticfeedback control signal applied at soldering point 340 may causepiezoelectric disk 322 to expand or stretch in embodiments herein. Thismay, in turn, cause the metallic layer or disk 325 adhered to theceramic piezoelectric disk 322 to warp upward. The principle of hapticsapplied to the piezoelectric disk 322 includes an input voltage that isapplied through the two electrodes (voltage change as sine wave, squarewave etc.) to generate movement on piezoelectric material 322 of thepiezoelectric element 320 and a warping of the metallic layer or disk325. One or more haptic feedback control signal in an embodiment maycomprise a haptic tactile movement feedback control signal for causinghaptic movement feedback at the piezoelectric element 322, a hapticsound feedback control signal for causing haptic sound feedback at thepiezoelectric element 322 through one or more frequencies of upward anddownward movement, or a single haptic feedback control signal forcausing both haptic movement feedback and haptic sound feedback,simultaneously, at the piezoelectric element 322.

In example embodiments herein, one or more haptic movement feedbackcontrol signals may be used to cause a haptic movement feedback such asa depression and return of the key 300 or a tactile “click” or movementof a touchpad according to a plurality of types of haptic feedback toindicate which level of force has been applied to extended action keysor an extended action touchpad. The type of haptic feedback sent to anactuated piezoelectric element in example embodiments may indicate whichfunction of a selection of multi-level functions or which character froma selection of characters has been selected with the applied force levelto the extended action key 300 or extended action touchpad.

Further, the haptic sound feedback control signal may be used to causeone or more types of haptic sound feedback such as an audible clickingor buzzing sound in some embodiments. For example, movement of thepiezoelectric element 320 from a planar or neutral position to an upwardor downward position, or between an upward warped position and downwardwarped position may generate audible sound waves. The pitch and volumeof such sound waves in an embodiment may depend, at least partially, onvarious adjustable aspects (e.g., frequency, magnitude, polarity ofvoltage) of the haptic feedback control signal. Such a haptic soundfeedback control signal, such as a sine wave signal, or other hapticfeedback control signals with varying polarities or voltage and currentmay be used by the keyboard controller to create the haptic feedback(e.g., haptic movement feedback or haptic sound feedback) felt or heardby the user as described herein.

FIG. 3E is a side cut-out view of an extended action key 300 of a hapticfeedback keyboard implementing a piezoelectric element in an upwardwarped position according to an embodiment of the present disclosure. Asdescribed herein, upon receiving one or more piezo actuation signallevels or other haptic actuation indicator signal, the controller (notshown) in an embodiment may send one or more corresponding hapticfeedback control signals to the piezoelectric element 320 via the metaltraces formed on the contact foil 310, through the soldering points 335and 340 and to a conductive layer of metallic plate or ring 325 formedbelow the piezoelectric disk material 322 to cause a haptic movementfeedback or haptic sound feedback. As described herein, the type ofhaptic movement feedback or haptic sound feedback sent to the extendedaction key 300 or extended action touchpad may indicate the level ofactuation press and selection of one function or character from aplurality of available functions or characters associated with theextended action key 300 or extended action touchpad. The conductivelayer of metallic plate or ring 325 may apply the haptic feedbackcontrol signal to the piezoelectric disk material 322 so as to cause thepiezoelectric disk material 322 to stretch or shrink depending on thepolarity of the signal applied. For example, reversing polarity ofvoltage applied by a haptic feedback control signal to the piezoelectricdisk 322 as described with reference to FIG. 3E may cause thepiezoelectric disk 322 to compress or shrink and metallic plate 325 maywarp upwards. More specifically, a positive voltage haptic feedbackcontrol signal applied to piezoelectric disk material element 322 atsoldering point 335 relative to a negative voltage haptic feedbackcontrol signal applied at soldering point 340 may cause piezoelectricdisk 322 to stretch or expand in embodiments herein. This may, in turn,cause the metallic layer or disk 325 adhered to the ceramicpiezoelectric disk 322 to warp upward. By oscillating the voltage (e.g.,reversing polarity) of the haptic feedback control signals applied tothe soldering points 335 and 340 in such a way, the controller in anembodiment may cause the piezoelectric element 320 to move between itsupward warped position and downward warped positions as shown in FIGS.3D and 3E. Such a movement of the metallic plate or disc 325 in anembodiment may generate various types of tactile movement hapticfeedback or audible sound waves depending on various frequencies andmagnitude of the haptic feedback control signal to the piezoelectricelements. Thus, the warping of the piezoelectric elements associatedwith the extended action key 300 or an extended action touchpad asdescribed may be used to generate tactile haptic feedback events as wellvia haptic feedback control signals in embodiments herein.

FIG. 4 is an exploded perspective view of a keyboard stack up 400 of aninformation handling system according to an embodiment of the presentdisclosure. The keyboard stack up 400 shows a plurality of keys, similarto those described in connection with FIGS. 3A-3E above, arranged so asto receive input from a user at multiple keys. FIG. 4 also shows a topcoversheet 405 having both a keyboard 401 and a touchpad 402. Either orboth of the keyboard 401 and touchpad 402 may be haptic systems asdescribed in embodiments herein and either or both may include use ofincluding extended action keys in the haptic keyboard 401 or an extendedaction haptic touchpad 402 of embodiments herein. In an embodiment, thekeys may be arranged similar to a QWERTY design of a keyboard 401.However, other arrangements of any alphabetic, numeric, or symbolic keysis contemplated by the present description. In the extended action keyhaptic feedback keyboard and touchpad control system of the haptickeyboard and touchpad control system, more than one alphanumericcharacter may be available and associated with a particular extendedaction key even without requiring a simultaneous press of a shift key oran alt key. Thus, the number of keys in the layout design of thekeyboard 401 may be streamlined or reduced in size in variousembodiments herein using one or more extended action keys to optimizethe keyboard space formed on the information handling system. An exampleoptimized keyboard layout is depicted and described with respect to FIG.10 below. Fewer keys may be utilized with equal or greater functionalityleaving more space on a C-cover for a touchpad or other functionality.Further, fewer keys may also allow for fewer piezo key stackups neededallowing for more space in the base chassis or for a thinner, morestreamlined information handling system.

The keyboard stack up 400 may include several layers similar to thosedescribed in connection with FIGS. 3A-3E. In an embodiment, the keyboardstack up 400 includes a coversheet layer 405. The coversheet layer 405may be made of any type of elastically resilient material. Coversheetlayer 405 may include a plurality of key designations, such as keypedestals as shown in keyboard 401 and a touchpad 402 area designation.In an example embodiment, the key designations may provide an indicationof a plurality of available alphanumeric characters or functionsselectable by an extended action key. In other embodiments, the keydesignations may also provide an indication of a plurality of availablealphanumeric characters or functions selectable by via any shift orfunction key in addition to those available via various press levels forthe extended action key. The elastically resilient material may allow,at least, a portion of the coversheet layer 405 to be deformed uponapplication of a pressure from a user's finger. Upon withdraw of thepressure from the user's finger, the material the coversheet layer 405is made of allows the coversheet layer 405 of the key to bend back toits pre-deformed form. In an embodiment, the resilient material mayallow the coversheet layer 405 to travel a distance of between 0.01 mmand 2 mm. The range of available travel distance of the coversheet layermay accommodate actuation at two or more downward force actuation levelson an extended action key in some embodiments.

In an embodiment, the shape of the coversheet layer 405 may be such soas to conform to the user's fingers. In an embodiment, in order to shapethe coversheet layer 405, the material used to form the coversheet layer405 may be subjected to an injection molding process. As such, a topportion of the coversheet layer 405 may be formed to be ergonomicallybeneficial to a user's actuation such as by providing a tactile keylocation designation and conforming to the user's fingers, for example.The injection molding process may be completed prior to the installationof the coversheet layer 405 into the remaining layers within thekeyboard as described herein. Any number of processes may be includedwith the injection molding process. In an embodiment, the injectionmolding process used to form the coversheet layer 405 may includeforming a number of holes within a sheet of, for example, ABS. Theseholes may correlate with each actuatable key to be formed on thekeyboard 401. The formation of the coversheet layer 405 may continuewith injection molding a translucent ABS through the holes to form araised portion for key pedestals correlating with each of the number ofkeys on the keyboard 401. The raised portion for the key pedestals mayinclude different and various materials used to form the raisedportions. In an embodiment, the raised portions may be made of a fabric,silicone, or polycarbonate or combinations thereof. In an embodiment,the raised portion may include a fabric top layer with a polycarbonateinsert bonded below the fabric top layer. In an embodiment, the raisedportion may include a silicone or polycarbonate top layer with apolycarbonate insert bonded below the silicone or polycarbonate toplayer. In an embodiment, the raised portion may include a polycarbonatetop layer with a metal insert bonded below the polycarbonate top layer.In an embodiment, the raised portion includes a polycarbonate top layerwith a silicone core bonded to the polycarbonate top layer. In each ofthese embodiments, the raised portion may be formed using an injectionmolding process, a compression molding process an insertion moldingprocess, and a liquid silicone rubber (LSR) injection molding process,among other types of processes.

Opposite the raised portions a number of runners may be machined away toaccommodate for receipt of other layers of the keyboard such as each ofthe piezoelectric elements 420. The surface of the coversheet layer 405on which the raised portions of key pedestals are formed may be paintedand any number or type of graphics may be laser etched on each raisedportion indicating a specific key of the keyboard 401. As described, itis also contemplated that coversheet layer 405 may include a pluralityof key vias for keys of the static keyboard of the present embodimentsto be disposed through in some example embodiments. Similarly, it iscontemplated that coversheet layer 405 may include a touchpad via as awindow for a touchpad interface surface of a solid-state touchpadaccording to embodiments herein to be accessible in some aspects. Anycombination of the above coversheet 405 layouts described iscontemplated in embodiments described herein.

The keyboard stack up 400 may further include a C-cover substructure 435forming part of the base chassis with a cutout for keyboard 401 andtouchpad 402. In an embodiment, the touchpad 402 and coversheet layer405 may form a monolithic piece that, for example, includes differentpolycarbonate-acrylonitrile butadiene styrene (PC-ABS) resins used tocosmetically differentiate the touchpad 402 from a remaining portion ofthe coversheet layer 405. In an embodiment, the different PC-ABS mayinclude chemical properties that differentiates the touchpad 402 portionto the coversheet layer 405 via other properties such as stiffness. Inan embodiment, the coversheet layer 405 may be expanded to extend overan area where a user may rest the user's palms against the informationhandling system often referred to as a palm rest. In an embodiment, thecoversheet layer 405 may be expanded over the area of the palm restthrough a material such as a glass. In this embodiment, the glass may beattached to a remaining portion of the C-cover substructure 435 througha bonding process or via metal inserts attached to glass and connectedto the C-cover substructure 435 through a number of fastening devices.

In an embodiment, the C-cover substructure 435 may be made of a rigidmaterial that prevents little or no movement. The rigidity of theC-cover substructure 435 allows the other layers within the keyboard 401to be maintained within the information handling system. In anembodiment, the C-cover substructure 435 may be made to a metal.

The keyboard stack up 400, in an embodiment, may further include anynumber of adhesive layers 415. In an embodiment, a first adhesive layer415 may mechanically couple the coversheet layer 405 to a contact foillayer 410. The first adhesive layer 415 may be include the placement ofthe adhesive at locations that may enhance the movement and prevent thehinderance of the actuation of the coversheet layer 405 at thoselocations across the coversheet layer 405 where keys are present. In aspecific embodiment, the first adhesive layer 415 may include placingthe adhesive along borders of each of the keys as well as placing theadhesive at a central location of each of the keys.

The contact foil layer 410 is adhered to the coversheet layer 405 viathe first adhesive layer 415 may be made of any elastically resilientmaterial that, when any given key is actuated or the contact foil layer410 is bent towards a lower portion of the respective key, returns toits original state when the respective key is no longer being actuated.The contact foil layer 410 may include a number of metal traces 445formed thereon that electrically and communicatively couples each of thekeys and a corresponding piezoelectric element 420 to a controller 425of an information handling system that includes a haptic feedbackkeyboard control system such as described in connection with FIG. 1. Inan embodiment, the controller 425 may be a dedicated controller 425communicatively coupled to the contact foil layer 410 so as to detectone or more levels of electrical charges from each of the piezoelectricelements 420 and provide one or more types of haptic feedback controlsignals back to the respective piezoelectric elements 420 according tovarious embodiments herein. In an alternative embodiment, the controller425 may be a processor of the information handling system that, amongother computations and execution of other computer readable programcode, also executes computer readable program code associated with thehaptic feedback keyboard control system as described in FIG. 1.

During operation of each key on the keyboard 401, the contact foil layer410 may receive an electrical charge from the respective piezoelectricelements 420 as they are compressed upon actuation at the metal traces445 that conduct the electrical charge to the controller 425 associatedwith the keyboard 400. The charge magnitude levels of the actuationsignal may vary depending on the level of mechanical stress applied tothe extended action key in some embodiments herein and these levels ormagnitudes may be received by the metal traces 445. The metal traces 445formed on the contact foil layer 410 may further be used to conduct areturn electrical haptic response signal from the controller 425 to thepiezoelectric elements 420 so that the voltage and current of the returnhaptic feedback control signal may cause the piezoelectric elements 420to stretch or contract in response to a control haptic feedback signaland at varying polarities, voltages, or currents. This electricalresponse haptic feedback control signal to each of the actuatedpiezoelectric elements 420 may cause a haptic feedback presented at eachof the keys that the user may feel. In some embodiments herein,selection from among several types of haptic feedback may be providedvia return haptic feedback control signals depending upon the level ofmechanical stress applied to the piezoelectric element during actuation.Plural electric charge threshold levels for actuations of an extendedaction key and the piezoelectric element associated with it may be usedto determine the type of haptic feedback provided to the actuatedextended action key corresponding to the level selected in someembodiments herein. This haptic feedback may be relayed to the userwithin microseconds of the user actuating any of the keys on thekeyboard 401 such that the user physically detects a sensation that theextended action key was pressed and what level was selected. Thissensation felt by the user may be present despite no actual mechanicaldevices such as a scissor mechanism or other types of keyboardmechanical devices being present among the layers of the keyboard 401.

The keyboard stack up 400 may further include a second adhesive layer416 that mechanically couples the contact foil layer 410 to a supportplate 430. In an embodiment, the second adhesive layer 416 may includethe placement of an adhesive along borders of each piezoelectric element420 of the keyboard stack up 400. As shown in FIG. 4, the secondadhesive layer 416 includes circular voids that conform to a shape ofeach piezoelectric element 420 within the keyboard stack up 400.

The support plate 430 may be made of rigid material such as a metal. Thesupport plate 430 prevents deformation of the keyboard stack up 400except for, in some embodiments, the contact foil layer 410,piezoelectric element 420, first adhesive layer 415, and second adhesivelayer 416 as for operation of the haptic keys. As such, the contact foillayer 410 may be allowed to detect the deformation of the piezoelectricelements 420 to the various mechanical stress levels described forselecting multi-level functions or characters available at the extendedaction key. Additionally, a user using the keyboard 401 may feel a levelof rigidity in the keyboard 401 except that at the locations of the keyswhere the user has expected that some level of deformation occurs whenpressure is applied to provide for key actuation of the piezoelectricelement 420.

In an embodiment, the support plate 430 may include a number of cavities431 formed therein. The cavities 431 may be sized to have a relativelysmaller diameter than the diameter of each of the respectivepiezoelectric elements 420. By including these cavities 431, thepiezoelectric elements 420 may be allowed to be deformed into thecavities 431 so that the deformation of the piezoelectric element 420creates the electrical charge described herein. The metal plate of thepiezoelectric elements 420 may have a diameter greater than cavities431. Upon compression or contraction of the piezoelectric materialportions, such as a ceramic disk of the piezoelectric element 420, themetal plate may warp into or away from the cavity 431. The depth of thecavities 431 may also be selected to allow for at least a centralportion of each piezoelectric element 420 to be deflected into thecavities 440 some distance. This distance of deflection, in anembodiment, may be 0.1 mm or smaller or may be greater. In embodimentsherein, the deflection may accommodate two or more levels of deflectiondue to mechanical stress for use with extended action keys according toembodiments herein. In an embodiment, the cavities 431 may also be holespunched or machined through the support plate 430.

In an embodiment, the support plate 430 may be secured to other rigidelements of the information handling system. In an embodiment, thesupport plate 430 may be secured to the C-cover substrate 435 via anumber of bolts, screws, or other mechanical or chemical couplingdevice. In some embodiments, the support plate 430 may be operativelycoupled to the D-cover of the information handling system.

Each of the piezoelectric elements 420 may include a first portion layerof piezoelectric material and a second portion conductive layer asdescribed herein in connection with the larger figures describing thekeys in FIGS. 3A and 3B. Additionally, each piezoelectric element 420 ofthe keyboard 401 may be operatively coupled to at least one metal trace445 formed on the contact foil layer 410 via a contact point such as asolder point. In this embodiment, the conductive layer associated witheach of the piezoelectric materials of the piezoelectric elements 420may be operatively coupled to at least one metal trace 445 formed on thecontact foil layer 410 via a contact point such as a solder point. Thecontact foil layer 410 may, in a particular embodiment, include twometal traces 445 for each piezoelectric element 420 at a first portionand a second portion formed in the keyboard 401.

During operation of the keyboard 401, a user may actuate a key formed onthe coversheet layer 405 of the keyboard 401 by pressing down on thatkey. As a result of the mechanical stress placed on the piezoelectricmaterial of the piezoelectric element 420 associated with the actuatedkey, an electric charge is created at the piezoelectric element 420. Theelectric charge is an actuation signal and may have varying magnitude ofelectric charge or levels of charge relative to mechanical stress at thepiezoelectric element 420 due to actuation force on an extended actionkey in example embodiments. The electrical charge is carried to one ormore metal traces 445 coupled to the piezoelectric material and themetal plate of the piezoelectric element 420 via a contact point such asa solder point. The electric charge received at the one or more metaltraces 445 may be conducted to a controller 425 by the metal trace 445as described herein. In this embodiment, the controller 425 may detectthat electrical charge produced by the mechanical stress of thepiezoelectric material of the piezoelectric element 420 and maydetermine a threshold level range of the applied mechanical stress assignaled in the electric charge actuation signal. Then the controllermay send a corresponding haptic feedback control signal back to thepiezoelectric material of the piezoelectric element 420 that isassociated with the received threshold range. This haptic feedbackcontrol signal may have a certain voltage, current, and polarity (−,+)sufficient to render the piezoelectric material of the piezoelectricelement 420 to cause a one of a selection of a plurality of types ofhaptic feedback event or sound. The haptic feedback control signal fromthe controller 425 may follow the same or a different metal trace 445back to the piezoelectric element 420. The haptic feedback controlsignal may be received at the piezoelectric material and metal plate ofthe piezoelectric element 420 via, for example, a contact point such asa solder point. Because the piezoelectric material of the piezoelectricelement 420 receives the haptic feedback control signal from thecontroller 425 this causes the piezoelectric material to be generate oneof the types of haptic feedback event. A response signal may be a sinewave, a square wave, a pulsed signal, or other waveform of changingcurrent, voltage, or polarity applied to the piezoelectric element 420.As a result of the piezoelectric material stretching or contractingduring the haptic event, the piezoelectric element 420 warp downward orupward with respect to the cavity 431 and may return back to anon-deformed state thereby creating haptic feedback felt by the user'sfinger. In an embodiment, the relay of the electrical charge to thecontroller 425, the detection of the controller 425 of the electricalcharge, and the return of the haptic feedback control signal by thecontroller 425 to the piezoelectric element 420 may be sufficientlyquick enough for the user to feel the haptic feedback in a manner thatthe user does not detect any temporal delay between the actuation of thekey and the detection of the haptic feedback created at thepiezoelectric element 420. Further, the type of haptic feedback eventprovided through an extended action key may indicate to the user whatlevel has been selected via the extended action key and, accordingly,what function or character may be selected from a plurality of the sameavailable through the extended action key. In an embodiment, the relayof the electrical charge to the controller 425, the detection of thecontroller 425 of the electrical charge, and the return of the hapticfeedback control signal by the controller 425 to the piezoelectricelement 420 may be on the order of microseconds. This operation of eachof the keys of the keyboard 401 may be conducted every time the useractuates any key or extended action key on the keyboard 401.

FIG. 5 is a series of sequential graphical views 501, 502, 503, 504, and507 depicting manufacture process 500 of a coversheet of a keyboardaccording to an embodiment of the present disclosure. The manufactureprocess 500 of the coversheet may be done so as to produce a layer thata user may come in contact with during use of the keyboard. In anembodiment, the shape of the coversheet may be such so as to conform toa user's finger.

The manufacture process 500 may begin at 501 with forming a number ofholes 530 within a sheet of ABS 505. These holes may correlate with anumber of keys on a keyboard. Although specific embodiments describethat the holes 530 are formed into a sheet of ABS 505, the presentspecification contemplates the use of other types of materials that areelastically resilient material that allows for deformation of thekeyboard upon application of a force but provides for the return of thematerial to a pre-deformed state after that force is removed.

The manufacture process 500 may continue at 502 with injection molding atranslucent ABS 515 through the holes 530 to form a raised portion askey pedestals 506 correlating with each of the number of keys on thekeyboard. In a backside view of coversheet 505 shown in 503, the raisedportions formed by the translucent ABS 515 may be machined away to forma number of runners 520 to accommodate for receipt of other layers ofthe keyboard. The manufacture process 500 may then include, on the topside of the coversheet 505 of ABS shown at 504, painting the coversheet505 and key pedestals 506 a selected color. At 507, any number or typeof graphics 525 may be painted or etched onto the surface of thecoversheet on which the raised portions of the translucent ABS areformed into key pedestals 506. In an embodiment, the keyboard may beformed out of a plurality of sheets of ABS 505 subjected to themanufacture process 500 described herein. In an embodiment, a singlesheet of ABS 505 may be subjected to the manufacture process 500described herein to form all of the keys of the keyboard of a coversheet505 a user is to interact with.

FIG. 6 is an exploded perspective view of a touchpad stack up 600 of aninformation handling system according to another embodiment of thepresent disclosure. As described herein, the touchpad stack up 600 mayalso have a touchpad that implements the piezoelectric elements 620described herein. The touchpad stack up 600 may represent an extendedaction touchpad according to embodiments herein. In other embodiments,the touchpad stack up 600 may have some portions of the touchpadinterface area designated to operate at an extended action touchpadwhile other portions are not. The touchpad may be formed, in someembodiments, into a touchpad cover area 602 in coversheet layer 605.Coversheet 605 may also have a number of keys of a keyboard 601.Coversheet 605 may have one or both the haptic touchpad 602 and haptickeyboard 601 in some embodiments. In other embodiments, either thehaptic touchpad 602 or keyboard 601 may be a conventional system. Forexample, a mechanical keyboard 601 may be implemented with a haptictouchpad 602. In another embodiment, the touchpad coversheet layer 605may be separate from any other coversheet layer such as for the keyboard601 or other portions of a C-cover.

The touchpad coversheet layer 605 with designated haptic touchpad area602 may be made of any type of elastically resilient material. Theelastically resilient material may allow, at least, a portion of thetouchpad coversheet layer 605 to be deformed upon application of apressure from a user's finger. Upon withdraw of the pressure from theuser's finger, the material of the touchpad coversheet layer 605 is madeof allows the touchpad coversheet layer 605 of the touchpad to bend backto its pre-deformed state. In an embodiment, the resilient material mayallow the touchpad coversheet layer 605 at haptic touchpad 602 to travela distance of between 0.01 mm and 2 mm.

The arrangement of the piezoelectric elements 620 for haptic touchpad602 described herein is also shown in FIG. 6. In the embodiment shown inFIG. 6, piezoelectric elements 620 are placed in an array under thetouchpad of the touchpad coversheet layer 605. The placement of thepiezoelectric elements 620 in the array under the touchpad surface 602of the touchpad coversheet layer 605 may include more or less than thenumber of piezoelectric elements 620 shown. As described herein, theoperation of the touchpad may be dependent on the location and number ofpiezoelectric elements 620. During operation, a controller (not shown)similar to the controller described in connection with FIG. 4 mayreceive an electric charge from one or a plurality of piezoelectricelements 620 formed below and across the touchpad area 620 of coversheetlayer 605 so that the controller may detect one or more piezoelectricelements 620 providing a signal depending on proximity underneath an x-and y-coordinate location of the actuation location on the touchpad bythe user. The receipt of one or a plurality of electrical charges fromthese piezoelectric elements 620 may allow the controller toappropriately send a return haptic feedback control signal to any of thepiezoelectric elements 620 so that the user may detect a haptic feedbackat the location where the user has actuated the haptic touchpad 602 ofthe coversheet layer 605. In embodiments herein, the one or morepiezoelectric elements 620 under an extended action touchpad area maygenerate an electrical charge actuation signal of varying magnitudedepending on the magnitude of charge which may correspond to mechanicalstress applied to deflect the one or more piezoelectric elements. Thecontroller may receive the electrical charge actuation signal anddetermine whether the actuation signal falls within any of two or morethreshold ranges similar to embodiments described herein. In someembodiments, the threshold range reached may correspond to a function ora character designated for that level. Further, the threshold rangereached may also determine the type of haptic feedback returned to thehaptic touchpad actuation location via the actuated piezoelectricelement or elements. This type of haptic feedback may indicate whichlevel of function or character selected by the downward force applied toactuate the extended action touchpad in embodiments herein.

The coversheet 605 with haptic touchpad 602 may further include aC-cover substructure 635. The C-cover substructure 635 may be made of arigid material that prevents little or no movement. The rigidity of theC-cover substructure 635 allows the other layers within the touchpadstack up 600 to be maintained within the information handling system. Inan embodiment, the C-cover substructure 635 may be made to a metal.

The touchpad stack up 600, in an embodiment, may further include anynumber of adhesive layers 615. In an embodiment, a first adhesive layer615 may mechanically couple the touchpad coversheet layer 605 to acapacitive touch layer 655. The capacitive touch layer 655 may be madeof a rigid material such as a glass, biaxially-oriented polyethyleneterephthalate (BoPET) such as Mylar® produced by DUPONT®, or aglass-reinforced epoxy such as FR4 to serve a purpose as a stiffeninglayer as well. The capacitive touch layer 655 includes a grid of driveand sense lines to determine x- and y-touch locations on haptic touchpad602 by a user. The capacitive touch layer 655 may be placed within thelayers of the touchpad to distribute forces from a user's finger acrossthe surface of the touchpad coversheet layer 605 and to the nearest or aplurality of nearest piezoelectric elements 620 in the array formedbelow and across the bottom surface of the haptic touchpad 602 of thecoversheet layer 605 and capacitive touch layer 655. The stiffeningfunction of the capacitive touch stiffening layer 655 is an optionalembodiment as a rigidity of the haptic touchpad 602 may be provided byother layers as well in other embodiments.

The first adhesive layer 615 may be include the placement of theadhesive at locations that may enhance the movement and prevent thehinderance of the actuation of the touchpad coversheet layer 605 atthose locations across the touchpad coversheet layer 605 wherepiezoelectric elements 620 are present. In a specific embodiment, thefirst adhesive layer 615 may include placing the adhesive along bordersof each of the piezoelectric elements 620 as well as placing theadhesive at a central location of each of the piezoelectric elements620.

The contact foil layer 610 adhered to the touchpad coversheet layer 605via the first adhesive layer 615 may be made of any elasticallyresilient material that, when any given location at the touchpadcoversheet layer 605 is actuated or the contact foil layer 610 is benttowards a lower portion of the respective location, returns to itsoriginal state when the respective location is no longer being actuated.

In an embodiment, the contact foil layer 610 or the capacitive touchlayer 655 may include a capacitive touch layer x and y grid that detectsand measures anything that is conductive such as a user's finger. Thedrive lines and sense lines may be a grid of indium tin oxide (ITO) orother conductive materials arranged to detect capacitive changes at xand y locations across the capacitive touch layer that correspond to thetouch interface cover layer of the haptic touchpad 602. The capacitivetouch layer 655 may be a printed circuit board (PCB) layer for thedetection of the user's finger at an x- and y-coordinate location acrossthe surface of the area of the haptic touchpad 602 of the coversheetlayer 605. The capacitive touch layer 655 may be an array of drive linesand sense lines of ITO formed on the capacitive touch stiffening layer655 or on the contact foil 610 in an embodiment. Drive lines and senselines may be operatively coupled to a capacitive touch controller fordetermining x- and y-location of touches on the haptic touchpad 602. Thecapacitive touch layer can be part of the contact foil layer 610, or itsown contact touch layer 655, or part of a stiffener layer in variousembodiments.

The contact foil layer 610 may include a number of metal traces 645formed thereon that electrically and communicatively couples each of thelocations and corresponding piezoelectric elements 620 to a controller(not shown) of an information handling system that includes a hapticfeedback touchpad 602 control system such as described in connectionwith FIG. 1. Traces may be opposite the capacitive touch layer oncontact foil layer 610 in an embodiment. In an embodiment, thecontroller may be a dedicated controller communicatively coupled to thecontact foil layer 610 so as to detect a variety of levels of electricalcharges from the piezoelectric elements 620 and provide one of aplurality of types of haptic feedback control signals back to therespective piezoelectric elements 620. In an alternative embodiment, thecontroller may be a processor of the information handling system that,among other computations and execution of other computer readableprogram code, also executes computer readable program code associatedwith the haptic feedback keyboard control system as described in FIG. 1.

During operation of the touchpad, the contact foil layer 610 may receivean electrical charge from one or a plurality of piezoelectric elements620 operatively coupled underneath the metal traces 645 that conduct theelectrical charge at a varying magnitude level to the controllerassociated with the keyboard 600. The metal traces 645 formed on thecontact foil layer 610 may further be used to conduct a return hapticfeedback control signal associated with a corresponding type of hapticfeedback to the level selected from the controller to the piezoelectricelements 620 so that the voltage and current of the return hapticfeedback control signal may cause the piezoelectric elements 620 toreturn to a type of haptic feedback event to the touchpad actuation area602 that corresponds to the level selected by the actuation. This hapticfeedback event of the actuated piezoelectric elements 620 may cause ahaptic feedback presented at the actuation location along the touchpadcoversheet layer 605 that the user may feel. As described, the responsehaptic feedback control signal may be a sine wave, a square wave, apulsed signal or other variations of voltage or polarity changes togenerate a warping of a metal plate for the haptic feedback event. Thishaptic feedback may be relayed to the user within microseconds of theuser actuating a location on the touchpad area 602 of the coversheetlayer 605 such that the user physically detects a sensation that thetouchpad coversheet layer 605 was pressed. This sensation felt by theuser may be present, despite no actual mechanical devices, such as aclick switch mechanism, a touchpad trigger, or other types of touchpadmechanical devices being present among the layers of the touchpad stackup 600. The haptic event in particular may feel like a click, a deeperclick, or multiple clicks similar to a mechanical switch click upon apress for selection by a user in some various embodiments of types ofhaptic feedback.

The touchpad stack up 600 may further include a second adhesive layer616 that mechanically couples the contact foil layer 610 to a supportplate 630. In an embodiment, the second adhesive layer 616 may includean adhesive that includes the placement of an adhesive along borders ofeach piezoelectric element 620. As shown in FIG. 6, the second adhesivelayer 616 includes circular voids that conform to a shape of eachpiezoelectric element 620 placed below the touchpad area 602 of thecoversheet layer 605.

The support plate 630 may be made of rigid material such as a metal. Thesupport plate 630 prevents deformation of the touchpad stack up 600except for, in some embodiments, actuation levels of deformation at thecontact foil layer 610, piezoelectric elements 620, the first adhesivelayer 615, second adhesive layer 616, and other relevant layers asdescribed. As such, the contact foil layer 610 may be allowed to detectthe deformation of the piezoelectric elements 620. Additionally, a userusing the touchpad stack up 600 may feel a level of rigidity in the areaof the haptic touchpad 602 that the user actuates with the piezoelectricelements 620 providing a haptic event to mimic the deformation to occurwhen pressure is applied.

In an embodiment, the support plate 630 may include a number of cavities631 formed therein. The cavities 631 may be sized to have a relativelysmaller diameter than the diameter of each of the respectivepiezoelectric elements 620. By including these cavities 631, thepiezoelectric elements 620 may be allowed to be deformed into thecavities 631 so that the deformation of the piezoelectric elements 620creates the electrical charge described herein to detect actuation. Thedepth of the cavities 631 may also be selected to allow for at least acentral portion of each piezoelectric elements 620 to be deflected intothe cavities 631 some distance. This distance of deflection, in anembodiment, may be 0.1 mm or smaller or greater according to embodimentsherein.

In an embodiment, the support plate 630 may be secured to other rigidelements of the information handling system. In an embodiment, thesupport plate 630 may be secured to the C-cover substructure 635 via anumber of bolts, screws, or other mechanical or chemical couplingdevice. In some embodiments, the support plate 630 may be a part of theD-cover of the information handling system.

Each of the piezoelectric elements 620 may include a layer ofpiezoelectric material and a conductive metal plate layer as describedherein in connection with the larger figures describing the keys inFIGS. 3A and 3B, in FIG. 8, and in other embodiments herein.Additionally, each piezoelectric element 620 of the touchpad stack up600 may be operatively coupled to at least one metal trace 645 formed onthe contact foil layer 610 via a contact point such as a solder point.In this embodiment, the conductive metal plate and the piezoelectricmaterials of the piezoelectric elements 620 may each be operativelycoupled to at least one metal trace 645 formed on the contact foil layer610 via a contact point such as a solder point. Thus, the contact foillayer 610 may, in an embodiment, include two metal traces 645 for eachpiezoelectric element 620 formed in the keyboard 600.

During operation of the touchpad of the keyboard 600, a user may actuatea location across the touchpad area 602 of the coversheet layer 605 bypressing down on that location of the touchpad coversheet layer 605. Asa result of the mechanical stress placed on the location of the touchpadarea 602 of the coversheet layer 605, one or more piezoelectricmaterials of the piezoelectric elements 620 associated with a locationor neighboring locations of the actuation location may be compressed.This compression of the piezoelectric element 620 may create an electriccharge indicating actuation. In some embodiments, this electrical chargeactuation signal may have varying magnitude or multiple levelscorresponding to the level of compression applied to the one or morepiezoelectric elements. The electrical charge is carried to one or moremetal traces 645 coupled to the piezoelectric elements 620 via contactpoints such as solder points. The electric charge received at the metaltrace 645 may be conducted to a controller (not shown) by the metaltraces 645 as described herein. In this embodiment, the controller maydetect that electrical charge produced by the mechanical stress of thepiezoelectric material of the piezoelectric element 620 indicatingactuation and where the actuation occurred. Further, the level ormagnitude of the electrical charge received may be interpreted todetermine a level of function or alphanumeric character associated withan interface area of an extended action touchpad area in someembodiments. Then the controller may send a haptic feedback controlsignal back to the piezoelectric material of the piezoelectric element620. This electrical response signal may have a certain voltage,current, and polarity sufficient to cause a stretching or contractionresponse to generate a haptic feedback event as described in variousembodiments herein. Further, in some embodiments, several types ofhaptic feedback events may be generated at an actuation location of anextended action touchpad area to indicate a level of function orcharacter selection selected by the pressure applied to the extendedaction touchpad. The haptic feedback control signal from the controllermay follow the same metal traces 645 back to the given piezoelectricelement 620. The haptic feedback control signal may be received at aconductive layer of the piezoelectric element 620 via, for example, thecontact points such as the solder points. As a result of thepiezoelectric material may be made rigid and the piezoelectric element620 may return back to a non-deformed state thereby creating hapticfeedback felt by the user's finger. This haptic feedback effect may be aclick mimicking a mechanical click switch. At a second level of pressureapplied to correspond to a second function or character selection, adeeper click, a double click or more clicks, or a vibration or toneaccompanying the click may be the second level type of haptic feedbackeffect in some embodiments. In an embodiment, the relay of theelectrical charge to the controller, the detection of the controller ofthe electrical charge, and the return of the haptic feedback controlsignal by the controller to the piezoelectric element 620 may besufficiently quick enough for the user to feel the haptic feedback in amanner that the user does not detect any temporal delay between theactuation touchpad coversheet layer 605 and the detection of the hapticfeedback created at the or a plurality of piezoelectric elements 620. Inan embodiment, the relay of the electrical charge to the controller, thedetection of the controller of the electrical charge, and the return ofthe haptic feedback control signal by the controller to thepiezoelectric element 620 may be on the order of microseconds.

Unlike the individual keys of described in connection with the haptickeyboard of FIGS. 3A and 3B, however, the individual piezoelectricelements 620 may cooperate within the array to create the hapticfeedback felt by the user at the touchpad coversheet layer 605. In somespecific embodiments, the location of actuation by the user may bedetected by the capacitive touch layer (either integrated into thecontact foil layer 610, a separate capacitive touch layer 655, or with astiffening layer) to indicate to the controller which piezoelectricelements 620 should receive a return haptic feedback control signal.Along with the receipt of an electrical charge from the piezoelectricelements 620, the controller may cause that all or a portion of thetouchpad area forming the coversheet layer 605 receive haptic feedback.In some embodiments, the haptic touchpad area 602 may be divided up andmarked or designated as extended action touchpad areas of different setsof functions or character for auxiliary keys that may be designated withthe right level of actuation, and some touchpad areas that are notextended action touchpad areas in various embodiments. This may allowthe haptic feedback to be felt by the user across the entire surface ofthe touchpad area 602 of the coversheet layer 605, across a left side ofthe touchpad area 602 of the coversheet layer 605, across a right sideof the touchpad area 602 of the coversheet layer 605, across a topportion of the touchpad area 602 of the coversheet layer 605, across abottom portion of the touchpad area 602 of the coversheet layer 605, orany specific area across the surface of the touchpad area 602 of thecoversheet layer 605. In some embodiments, only a piezoelectric element620 directly under the touch location or only piezoelectric elements 620next to the nearest piezoelectric element 620 under the touch locationmay provide a haptic feedback event. Along with the capacitive touchlayer, the piezoelectric elements 620 may allow a user to have theuser's touch be detected at the touchpad while actuation, at anylocation across the surface of the touchpad coversheet layer 605provides haptic feedback to the user so that the user can engage in a“click” action at the touchpad such as when selecting an item on agraphical user interface or a second level haptic feedback type wheninvoking a second level function or character.

In an embodiment, the keyboard 600 may, once the layers described hereinare coupled together, may be placed within the C-cover 635 with aD-cover 665 coupled thereto. The assembly of the coversheet 605, C-coversubstructure 635, and the D-cover 665 forms a base chassis of theinformation handling system. In an embodiment, the base chassis may becoupled to a display chassis 650 that may include a display device. Thetouchpad stack up 600 described herein may allow the user to provideinput to the display device of the display chassis using the capacitivetouch layer, the piezoelectric elements 620 determining actuation, andthe haptic feedback capabilities associated with the piezoelectricelements 620. By way of example, the capacitive touch layer may allow auser to move a cursor across the screen. In these examples, actuation ofthe touchpad coversheet layer 605 at a location across the touchpadcoversheet layer 605 causes an item to be selected that is representedon the display device. This “click” action may provide similar input tothe processor of the information handling system similar to that of amouse click.

FIG. 7 is back perspective view of a C-cover 705 of an informationhandling system 700 according to an embodiment of the presentdisclosure. The C-cover 705 may be used to house a keyboard and touchpadas described herein. As also described, each of the keyboard andtouchpad may include a support plate 731 and 732, respectively. In anembodiment, a single support plate may be used to support one or more ofthe keyboard piezoelectric assemblies described in connection with FIGS.3A-3E and FIG. 4 or the touchpad piezoelectric assembly described inconnection with FIG. 6. In an alternative embodiment, the keyboardpiezoelectric assemblies and the touchpad piezoelectric assembly mayeach include their own support plate 731 and 732, respectively. Thesupport plates of the C-cover 705 shown may increase the stiffness ofthe haptic keyboard and touchpad described herein because the supportplates 731 and 732 may be firmly fixed to the C-cover 705. This mayenhance the perceived quality of the information handling system whilestill having a haptic feedback method and system that allows the user tofeel as if an actuation of a key or touchpad has occurred. Stillfurther, the haptic feedback systems described herein creates a keyboardor touchpad that feels like a mechanical keyboard vastly reducesphysical key travel. Additionally, the construction of the hapticfeedback systems described herein results in a much thinner and simplerkeyboard and touchpad than that of a mechanical keyboard or touchpadenabling a thinner information handling system in some embodiments. Withthe reduction in space occupied by the haptic feedback keyboard andtouchpad, space within the information handling system base chassis maybe increased for use by other, additional, or larger components withinthe information handling system. In a specific example embodiment, theadditional space provided within the information handling system due tothe use of a haptic feedback keyboard and touchpad results in theability to increase the size of a battery used to power the informationhandling system.

As shown in FIG. 7, the C-cover 705 may include both a piezoelectrickeyboard portion secured to the C-cover 705 by a first support plate 731and a touchpad portion being secured to the C-cover 705 by a secondsupport plate 732. In an embodiment, it is contemplated that thetouchpad and keyboard as described herein may be secured to the C-cover705 by a single support plate that combines 731 and 732. In theseembodiments, the keyboard and touchpad may both be operated using thepiezoelectric elements as described herein.

FIG. 8 is a top view of a piezoelectric element 800 according to anembodiment of the present disclosure. As described, the piezoelectricelement 800 may be incorporated into a key of the keyboard or atouchpad. In the embodiments described herein, any number ofpiezoelectric elements 800 may be incorporated into the informationhandling system so as to provide haptic feedback to a user.

In an embodiment, the piezoelectric element 800 includes a layer ofpiezoelectric material 820. This layer of piezoelectric material 820 maybe made of any piezoelectric material including crystals, ceramics,biological matter, protein layers, among other types of materials. Forease of explanation, the layer of piezoelectric material 820 may be madeof a ceramic or a crystal material although the present specificationcontemplates the use of other types of materials in differentembodiments.

As described herein, the layer of piezoelectric material 820 may beoperatively, and more specifically, electrically coupled to both acontact foil layer and the metal conductive layer 825. In an embodiment,the layer of piezoelectric material 820 may be electrically coupled tothe contact foil layer via a first electrical contact point 835. Thefirst electrical contact point 835 may, in an embodiment, be a solderingpoint that couples the layer of piezoelectric material 820 to a metaltrace formed on the contact foil layer. The metal conductive layer 825may be a brass metal plate or ring. Metal conductive layer 825 may beelectrically coupled to a trace on the contact foil layer via a secondelectrical contact point 850. First and second electrical contact points835 and 850 may be a solder point in an example embodiment. Underapplication of a mechanical stress on the layer of piezoelectricmaterial 820 resulting from a user actuating a coversheet layer abovethe piezoelectric element 800, the layer of piezoelectric material 820may create an electrical charge on metal conductor layer as it isdeformed or compressed, for example, into a cavity disposed below thepiezoelectric element 800. The electrical charge may be of varyingmagnitude or levels and correspond to an amount of mechanical stresscausing deformation of the piezoelectric element depicted. Thiselectrical charge may be passed to the metal traces via the firstelectrical contact point 835 and second electrical contact point 850 andmay be conducted to a controller as described herein.

Upon detection of the electrical charge from the layer of piezoelectricmaterial 820, the controller may send a haptic feedback control signalto the piezoelectric material layer 820 and the conductive layer 825 viametal traces formed on the contact foil layer. The haptic feedbackcontrol signal from the controller may be a variety of electricalresponse signals as described herein to cause the layer of piezoelectricmaterial 820 to return a haptic feedback event. The haptic feedbackevent may be felt by a user who caused the deformation of the layer ofpiezoelectric material 820 of the piezoelectric element 800 during theactuation of a key on a keyboard or a location on the touchpad.

Although FIG. 8 shows a specific shape and size of the piezoelectricelement 800 and conductive layer 825, the present specificationcontemplates that the piezoelectric element 800 may take on other formsand shapes as would serve a specific purpose in the operation of akeyboard or touchpad described herein.

FIG. 9 is a top view of a contact foil layer 900 of a keyboard of aninformation handling system embodiment of the present disclosure. Asdescribed herein, the contact foil layer 900 may include a contact foil910 may be made of any elastically resilient material that, when anygiven key or location on the touchpad is actuated or the contact foil910 is bent, the contact foil 910 returns to its original state when thecontact foil 910 is no longer subjected to a force used to bend thecontact foil 910. Contact foil layer 900 may be a flexible printedcircuit layer in an example embodiment.

The contact foil 910 of the contact foil layer 900 may be used tocommunicatively and electrically couple one or more piezoelectricelements 920 to a processor or other controller. As described herein,the piezoelectric elements 920 may be electrically coupled to a numberof metal traces via a first metal trace 945 and a second metal trace960. In a specific embodiment, a piezoelectric layer 921 of thepiezoelectric elements 920 may be electrically coupled to the firstmetal trace 945 via a first electrical contact point 935. Similarly, aconductive metal plate layer 925 of the piezoelectric elements 920 maybe electrically coupled to the second metal trace 960 via a secondelectrical contact point 950. The first electrical contact point 935 andsecond electrical contact point 950 may be, in an embodiment, a solderpoint.

The contact foil layer 900 may further include a serial communicationcoupling device 955. The serial communication coupling device 955 maycommunicatively couple the first metal trace 945 and second metal trace960, among other metal traces associated with each piezoelectricelements 920, to a processor or controller 932 for processing ofelectrical charges received from the piezoelectric layer 921 accordingto the embodiments described herein.

FIG. 10 is a perspective graphical diagram of an information handlingsystem 1000 with a haptic feedback keyboard 1001 and a haptic touchpadinterface 1002 depicting an optimized key layout according to an exampleembodiment of the present disclosure. Although FIG. 10 depicts theinformation handling system 200 as being implemented in a laptopcomputing device, FIG. 10 is not meant to be limiting and the presentspecification contemplates that the use of optimized key layouts of ahaptic keyboard 1001, such as the one shown, with other types ofinformation handling system as described. Other types of informationhandling systems may include smaller form factor information handlingsystems that may benefit from a more efficient layout of keys whilestill providing a full keyboard functionality by utilizing extendedaction keys or extended action touchpad which may provide auxiliary keys1009 at a designated extended action touchpad area of touchpad 1002 insome embodiments.

In the example of FIG. 10, the information handling system may include ascreen portion 1010 and a keyboard portion 1001 and touchpad portion1002 on a base chassis 1005. The screen portion 1010 may include anydevice that may present to a user any visual data as output to a user inresponse to input and execution of the instructions, parameters, andprofiles 124 by the processor 102 described in connection with FIG. 1which may reside in the base chassis 1005. In an example embodiment, agraphical user interface may be presented to a user to input any numberof parameters descriptive of the actuation force used level to actuateany number of extended keys 1020 including extended action keys such as1006, 1007, 1008 and 1020 on the keyboard portion 1001 of theinformation handling system, an actuation force at a location on anextended action touchpad 202, or both. The graphical user interface(GUI) may also be used to receive other settings including actuation ofa “click” when selecting items on display via a cursor using haptictouchpad 1002. The graphical user interface (GUI) may further be used toset the force required for actuation, setting multiple-levels of forceand operations associated with those levels, and selection of magnitude,pattern, or other characteristics of the haptic response by a key 1020or touchpad 1002 of the keyboard 1001.

The keyboard portion 1001 may include any number of keys 1020, such asextended action keys, arranged in any manner so as to receive input froma user via selective actuation of those keys 1020 including varyinglevels of applied force to select among levels of functions oralphanumeric characters associated with extended action keys 1020. In anembodiment, the keys 1020 may be arranged in a more optimized key layoutdue to the use of one or more extended action keys. For example, thekeyboard 1001 may be an optimized a QWERTY-type keyboard layout or anyother alphabetic, symbolic, or numeric layout. As compared to theQWERTY-type keyboard depicted in FIG. 2, the layout of keyboard 1001 ofFIG. 10, the one or more extended action keys may be used to streamlinethe number or layout of keys 1020 including eliminating the row offunction keys, eliminating the row of number keys, and eliminatingvolume up, volume down, page up, page down keys, caps lock keys, orother keys whose function may be rolled into one or more extended actionkeys 1020 or into auxiliary keys 1009 in designated extended actiontouchpad areas. In such embodiments, an optimized keyboard layout may beutilized to increase available space on a C-cover for the touchpad 1002or provide for smaller information handling systems to have fullerfunction keyboards. For example, extended action key 1006 may includethe letter j as well as extended action at a second level of actuationto select “&”. This and other keys like it may be used to roll the rowof number keys and punctuation and other characters normally across atop layer or second layer into a second level of extended action keys1020 such as shown in extended action key 1006. In another exampleembodiment, function key 1007 may be an extended action key with severallevels of extended action. Selection of more than two or more functionsmay be assisted by types of haptic feedback in some embodiments. Inother embodiments, selection of functions via extended action key 1007may be viewed on a portion displayed on a display screen. Such anextended action key as 1007 may eliminate one or more function keys thatmay appear across a top row in a typical QWERTY-type keyboard. In yetanother embodiment, the extended action key 1008 may be a shift key whenactuated and at a second level of applied actuation force may operate asa caps lock key. This may eliminate a caps lock key in an exampleembodiment. Many QWERTY-type keyboard keys may be consolidated similarto the example embodiments described here and any combination of keysinto and extended action key having any number of selectable levels iscontemplated in embodiments herein. In an embodiment, the keys 1020 maybe any number of keys from 1 to infinity. The extended action keys 1020of haptic keyboard 1001 and extended action touchpad 1002 including anyauxiliary keys 1009 at designated extended action touchpad locations mayoperate according to the embodiments of operation described with respectto any of the figures or as described included herein.

FIG. 11 is a flow diagram illustrating a method 1100 of operating ahaptic keyboard of an information handling system according to anembodiment of the present disclosure. The method of operating a haptickeyboard of FIG. 11 may include operation of extended action keys of thehaptic keyboard according to various embodiments herein. The method 1100may begin by receiving, at a piezoelectric element associated with a keyon a keyboard, a mechanical stress to create an electric charge at thepiezoelectric element at block 1105. As described herein, the actuationof the key of the keyboard causes a mechanical stress to be placed on apiezoelectric material layer of the piezoelectric elements. Thedeformation of the piezoelectric material layer results from theapplication of this mechanical stress which results in the creation ofthe electrical charge. Mechanical stress causes deformation of thepiezoelectric elements into a cavity disposed below at a support platesupporting the structures of the piezoelectric elements therebycompressing the piezoelectric material within the metal disk layer towhich it is adhered. According to embodiments herein involving anextended action key, the electric charge created by the mechanicalstress may be proportional to an amount of mechanical stress received atthe piezoelectric element associate with the extended action key. Thus,the greater level of actuation force applied to actuate the extendedaction key, the increased level of electric charge created. In this way,an increased level of force applied to the extended action key or adeeper key press may result in a higher charge level or magnitudegenerated at the piezoelectric element.

The method 1100 may continue, at block 1110, with conducting, to acontroller or processor, the electrical charge through a metal traceformed on a contact foil. The contact foil may be operatively coupled tothe piezoelectric device such that the charge formed at thepiezoelectric device of various charge levels may be allowed to conductthrough at least one metal trace formed thereon as an actuation signalto the controller or processor. In the embodiments described herein, twoconductors are connected to the piezoelectric material layer and themetal disk layer to detect the electric charge actuation signal.

The method 1100 may continue at block 1115 with determining with thecontroller or processor, that a first extended action key of thekeyboard has been actuated. The controller or processor may execute thehaptic feedback keyboard and touchpad control system according toseveral embodiments. The determination that a first extended action keyhas been actuated may be made based on the electrical charge signal thatthe processor receives from one or more specific metal traces formed onthe contact foil associated with the extended action key. Alternativeembodiments may be used to allow the processor to determine where andfrom which key on the keyboard the electrical charge is received from.Further, the charge level or magnitude of the actuation signal receivedat the controller or processor may be assessed as well.

Proceeding to decision block 1120, the controller or processor maydetermine the level or magnitude of the received electric chargeactuation signal from the piezoelectric element to compare with aplurality (N) threshold ranges of charge magnitude that correspond tolevels of pressure applied during actuation of the extended action key.For example, N threshold ranges may be available to be compared to thelevel of the electric charge actuation signal received at thecontroller. In an example embodiment, the N threshold ranges maycorrespond to N functions or alphanumeric characters available andassociated with the extended action key. Each N levels of actuationdepth or actuation signal charge level may correspond to N functions orcharacters in embodiments herein. For example, if the electric chargeactuation signal reaches a first threshold level, but less than a secondthreshold level, at the controller, flow may proceed to box 1125. If theelectric charge actuation signal passes a second threshold level, but isless than a next threshold level (e.g., a third level), if any, then theflow may proceed to box 1135. This may proceed up to a final Nththreshold level. The plurality of threshold levels may be set at two orany higher number. At the highest threshold level assessed at decisionbox 1120, if the electric charge actuation level exceeds the final Nththreshold level, then flow may proceed to box 1145. Each of theplurality of N threshold levels for electric charge may require a levelof keypress depth on the extended action key involving increasedkeypress force to deflect the piezoelectric element a greater amount.Further, the N threshold levels may be associated with N types of hapticfeedback to assist identifying which level has been selected and the Nthreshold levels may be correlated with N functions or alphanumericcharacters selectable by the extended action key.

At 1125, if the electric charge actuation signal exceeds the firstthreshold but not the next threshold electric charge level, the receivedelectric charge actuation signal is associated with a first levelfunction or alphanumeric character of the extended action key. The firstlevel selected alphanumeric character may be registered by the keyboarddriver with the operating application program in some embodiments. Inother embodiments, the first level selected function selected via theextended action key may be executed by the information handling systemprocessor. In some embodiments, the selected first level function oralphanumeric character selection may also appear on a display screen asa character in a program such as a word processing program or as a GUIindicating a selected function.

Proceeding to 1130, the controller may pass a first level hapticfeedback control signal back to the actuated piezoelectric element viathe metal trace of the contact foil to the first extended action key ofthe haptic keyboard according to embodiments herein. The first level ofhaptic feedback control signal may cause the upward or downward warpingof the piezoelectric element to exhibit the first level associated typeof haptic feedback. As described herein, the haptic feedback resultsfrom the haptic feedback control signal, at a determined voltage,current, or polarity being applied to the piezoelectric material layer.The response signal may be a sine wave, a square wave, pulsed signal, orotherwise varied and modulated to create a haptic event of a key pressfor the user. Application of the haptic feedback control signal to thepiezoelectric material layer causes the piezoelectric material layer tostretch, compress, or return to its non-deformed state in someembodiments.

This first type of haptic feedback may be felt by a user at the actuatedfirst extended action key and may indicate which level of the extendactions is selected. For example, types of haptic feedback may includethe stretched or compressed state of the piezoelectric material layermay create a haptic bump to be felt by the user at the extended actionkey actuated on the keyboard when the piezoelectric element metal platelayer is warped in response to the haptic feedback signal. In anotherexample embodiment, changing polarity and voltage levels in any portionof a haptic feedback signal may cause an expansion of the piezoelectricmaterial causing it to stretch and warp the metal plate layer into theunderlying cavity to feel like a mechanical key drop. This may bottomout and then may be followed by a haptic feedback signal of polarity andvoltage level to compress of the piezoelectric material and warp themetal plate away from the cavity to feel like a key return. In this way,a haptic event may mimic a mechanical keystroke at the actuated key onas feedback to a user's finger and may be a first type of hapticfeedback to indicate a first level selected. Any combination of theabove changes to the piezoelectric material may be generated by thehaptic feedback signal for causing the metal plate to warp and generatethe intended haptic feedback event to indicate a first level selection.The user actuation of the key to haptic feedback creation, may occurwithin microseconds of receiving an actuation signal. At this point themethod may end, however it may be repeated for each extended action keykeypress and for any extended action key among the haptic keyboard keys

Returning to decision box 1120, if the electric charge actuation signalexceeds a second threshold but not the next threshold electric chargelevel if there are more than two levels, flow may proceed to box 1135.At 1135, the received electric charge actuation signal is associatedwith a second level function or alphanumeric character of the extendedaction key. The second level selected alphanumeric character may beregistered by the keyboard driver with the operating application programin some embodiments. In other embodiments, the second level selectedfunction selected via the extended action key may be executed by theinformation handling system processor. In some embodiments, the selectedsecond level function or alphanumeric character selection may alsoappear on a display screen as a character in a program such as a wordprocessing program or as a GUI indicating a selected function.

Proceeding to 1140, the controller may pass a second level hapticfeedback control signal back to the actuated piezoelectric element viathe metal trace of the contact foil to the first extended action key ofthe haptic keyboard according to embodiments herein. The second level ofhaptic feedback control signal may cause the upward or downward warpingof the piezoelectric element to exhibit the first level associated typeof haptic feedback. As described herein, the haptic feedback resultsfrom the haptic feedback control signal, at a determined voltage,current, or polarity being applied to the piezoelectric material layer.The response signal may be a sine wave, a square wave, pulsed signal, orotherwise varied and modulated to create a haptic event of a key pressfor the user. Application of the haptic feedback control signal to thepiezoelectric material layer causes the piezoelectric material layer tostretch, compress, or return to its non-deformed state in someembodiments.

This second type of haptic feedback may be felt by a user at theactuated first extended action key and may indicate which level of theextend actions is selected. For example, types of haptic feedback mayinclude the stretched or compressed state of the piezoelectric materiallayer may create plural haptic bumps to be felt by the user at theextended action key actuated on the keyboard to indicate a second levelhas been selected with the applied keypress pressure level. The secondlevel haptic feedback may be generated when the piezoelectric elementmetal plate layer is warped in response to a second haptic feedbackcontrol signal. In another example embodiment, changing polarity andvoltage levels in any portion of a haptic feedback signal may cause anexpansion of the piezoelectric material causing it to stretch and warpthe metal plate layer into the underlying cavity to feel like a modifiedmechanical key drop which may pause, bump, click or otherwise indicatepassing through a stage before continuing with the feeling of a keydrop.If the second level is the last level, this keydrop haptic feedbacksensation may bottom out. The second type of haptic feedback may furtherfollow with by a haptic feedback control signal portion of polarity andvoltage level to compress of the piezoelectric material and warp themetal plate away from the cavity to feel like a key return. In this way,a haptic event may mimic a modified mechanical keystroke at the actuatedkey on as feedback to a user's finger to feel like a staged, “deeper”mechanical key actuation. This type or haptic feedback or any portion ormodification may serve as a second type of haptic feedback to indicate asecond level is selected. Any combination of the above changes to thepiezoelectric material may be generated by the haptic feedback signalfor causing the metal plate to warp and generate the intended hapticfeedback event to indicate a second level selection in variousembodiments. The user actuation of the key to haptic feedback creation,may occur within microseconds of receiving an actuation signal. At thispoint the method may end, however the method of FIG. 11 may be repeatedfor each extended action key keypress and for any extended action keyamong the haptic keyboard keys as referenced above.

Returning again to decision box 1120, if there are N=X threshold levelsand X is a final threshold level that is greater than to, flow mayproceed to box 1145 if the received electric charge level of theactuation signal exceeds the final N=Xth threshold level. As describedabove, embodiments herein contemplate two levels or any number of levelsgreater than two for the extended action key operations described inembodiments herein. For example, the haptic feedback keyboard andtouchpad control system may reference a lookup table to determine whichfunction or character is associated with an Nth level selection fromamong a plurality of functions or characters available with actuation ofthe extended action key in embodiments herein. This may occur for anythreshold level, whether the first level or the last level of allavailable selection levels for the extended action key.

At box 1145, if the electric charge actuation signal exceeded the N=Xthfinal threshold, the received electric charge actuation signal isassociated with a last level function or alphanumeric character of theextended action key. The last (Xth) level selected alphanumericcharacter may be registered by the keyboard driver with the operatingapplication program in some embodiments. In other embodiments, the last(Xth) level selected function selected via the extended action key maybe executed by the information handling system processor. In someembodiments, the selected last (Xth) level function or alphanumericcharacter selection may also appear on a display screen as a characterin a program such as a word processing program or as a GUI indicating aselected function.

Proceeding to 1150, the controller may pass a last (Xth) level hapticfeedback control signal back to the actuated piezoelectric element viathe metal trace of the contact foil to the first extended action key ofthe haptic keyboard according to embodiments herein. The last (Xth)level of haptic feedback control signal may cause the upward or downwardwarping of the piezoelectric element to exhibit the yet final levelassociated type of haptic feedback. As described herein, the hapticfeedback results from the haptic feedback control signal, at adetermined voltage, current, or polarity being applied to thepiezoelectric material layer. The response signal may be a sine wave, asquare wave, pulsed signal, or otherwise varied and modulated to createa haptic event of a key press for the user. Application of the hapticfeedback control signal to the piezoelectric material layer causes thepiezoelectric material layer to stretch, compress, or return to itsnon-deformed state in some embodiments.

This last (Xth) type of haptic feedback may be felt by a user at theactuated first extended action key and may indicate which level of theextend actions is selected. For example, types of haptic feedback mayinclude the stretched or compressed state of the piezoelectric materiallayer may create a bust of haptic bumps or a vibration for a period oftime to be felt by the user at the extended action key actuated on thekeyboard and different, in some embodiments from other types of hapticfeedback, The last (Xth) type of haptic feedback may be generated whenthe piezoelectric element metal plate layer is warped in response to thelast (Xth) haptic feedback control signal. In another exampleembodiment, changing polarity and voltage levels in any portion of ahaptic feedback signal may cause an expansion of the piezoelectricmaterial causing it to stretch and warp the metal plate layer into theunderlying cavity to feel like a mechanical key drop. This key dropfeeling may proceed through several pauses, clicks, bumps or otherstages such as X stages before reaching a final level in an exampleembodiment. The haptic feedback may bottom out and then may be followedby a haptic feedback signal of polarity and voltage level to compress ofthe piezoelectric material and warp the metal plate away from the cavityto feel like a key return. In this way, a haptic event may mimic amechanical keystroke at the actuated key on as feedback to a user'sfinger and indicated stages of depth of a keypress. Such an example typeof haptic feedback or any portion of the same may be the last (Xth) typeof haptic feedback to indicate a last level is selected. Any combinationof the above changes to the piezoelectric material may be generated bythe haptic feedback signal for causing the metal plate to warp andgenerate the intended haptic feedback event to indicate a last (Xth)level selection. The user actuation of the key to haptic feedbackcreation, may occur within microseconds of receiving an actuationsignal. At this point the method may end, but as described herein theprocess may be repeated for each extended action key keypress and forany extended action key among the haptic keyboard keys.

FIG. 12 is a flow diagram illustrating a method 1100 of operating atouchpad of an information handling system according to an embodiment ofthe present disclosure. The method 1200 may include, at block 1205, atleast one a piezoelectric element of an array of piezoelectric elementsassociated with a touchpad, a mechanical stress to create an electriccharge at the one or more piezoelectric elements. As described herein,the actuation of a location on the touchpad causes a mechanical stressto be placed on one or more piezoelectric material layers of thepiezoelectric elements in an array under the haptic touchpad. Thedeformation of the piezoelectric material layers may result from theapplication of this mechanical stress which results in the creation ofthe electrical charge. Deformation of the one or more piezoelectricelements into an underlying cavity formed in the support plate causescompression of the piezoelectric material. This compression may generatean electrical charge in the piezoelectric material layer. As describedherein, with extended action haptic touchpad operation, the electriccharge may be generated at varying levels depending on the compressivemechanical strain applied in actuation of the extended action touchpad.Increased touchpad actuation force may correspond to a higher level ormagnitude of electric charge in the actuation signal generated from atleast one piezoelectric element associated with the touchpad actuationlocation.

The method 1200 may continue with receiving, at a capacitive touch layerin the touchpad, x- and y-coordinate location data descriptive of atouch location of a user's finger across a surface of the touchpad atblock 1210. The x- and y-coordinate location data may be used by acontroller or processor in the described method 1200 to determine whichpiezoelectric elements to send an electric haptic response signal to. Inthese embodiments, the controller or processor may be provided withadditional data from a capacitive touch layer that provides theprocessor with a x- and y-coordinate location on the touchpad that theuser has touched in addition to the actuation signal of varying levelsfrom at least one piezoelectric element. Alternatively, or additionally,the number of piezoelectric elements actuated by the actuation of thetouch of the user may be used to allow the processor to determine where,on the touchpad, the user has touched.

The method 1200 may, at block 1215, continue with conducting, to acontroller or processor, the electric charge through metal traces formedon a contact foil. As described herein, the metal traces may be formedon a contact foil made of any elastically resilient material that, whenany given location on the touchpad is actuated or the contact foil isbent, the contact foil returns to its original state when the contactfoil is no longer subjected to a force used to bend the contact foil.For example, a flexible PCB may be used. Several examples of flexiblePCB may include photolithography metal on to a flexible PCB such as aPET material or lamination of metal traces within PET material. Otherflexible PCB or circuit materials are also contemplated.

The method 1200 may further include, with the controller or processor,determining that the touchpad has been actuated at decision block 1220.In this embodiment, the controller or processor may determine a locationalong the touchpad where the piezoelectric device from which theelectrical charge was received is located: across a left side of thetouchpad coversheet, across a right side of the touchpad coversheet,across a top portion of the touchpad coversheet, across a bottom portionof the touchpad coversheet, or any specific area across the surface ofthe touchpad coversheet. Further, the controller or processor may assessfrom the received electric charge that touchpad actuation has occurred.In some embodiments, for an extended action touchpad the controller orprocessor may assess the level of electrical charge actuation signalreceived for comparison to one or more threshold levels. For example,each level N may have a threshold electric charge threshold associatedwith the received in the extended action touchpad actuation signal thatmay be associated with selection of a level from among N level offunctions or characters in various embodiments. In some exampleembodiments, the location of the touch actuation may be at a designatedextended action touchpad location on the touchpad interface surface.This may be determined by the capacitive X-Y touch locationdetermination or by indication as to which piezoelectric element orelements in the array of touchpad piezoelectric elements have beenactuated by a press actuation. Different designated locations may havediffering sets of multi-level functions or available characters that maybe selected at each designated extended action location in varyingembodiments. For example, particular designated extended touch locationsmay serve as a regular touchpad at a first level and an auxiliary keywhen an extended action second level or higher level more is selected bya hard press at that location as shown in FIG. 10 at 1009.

If no received electric charge level at the controller or processorexceeds any threshold, the flow may return and continue to monitorelectric charge levels of actuation signals that may be received at1220. If, however, the electric charge level reaches a threshold level(e.g., an Nth threshold level) but is not higher than a next thresholdlevel (e.g., an N+1^(st) threshold level, if any), then flow may proceedto block 1225.

At block 1225, the controller or processor executing a haptic feedbackkeyboard and touchpad control system according to embodiments herein maydetermine which level N has been selected. It is understood that N maybe a first, second, third, fourth or any other selection level availablewith the extended action touchpad. The controller or processor may thusdetermine the function or character associated with the selection levelbased on the received electric charge level of the actuation signal. Forexample, the haptic feedback keyboard and touchpad control system mayreference a lookup table to determine which function or character isassociated with an Nth level selection from among a plurality offunctions or characters available with actuation of the extended actiontouchpad or a particular extended action touchpad designated location inembodiments herein. This may occur for any threshold level, whether thefirst level or the last level of all available selection levels for theextended action touchpad. The haptic feedback keyboard and touchpadcontrol system may register the Nth level function or characterselection and communicate that selection to the operating application orprocessor to appear as a character on the display screen or to causeexecution of a function such as selection of a cursor location on ascreen or invoking a dropdown menu at a point on a display screen.

Proceeding to block 1230, the controller or processor may pass a hapticfeedback control signal through to the piezoelectric element or elementsassociated with the actuation location on the touchpad causing hapticfeedback to be felt at the location on the touchpad. As described inembodiments herein, one type of haptic feedback control signal that isassociated with the selected Nth level, from among several hapticfeedback control signal options, may be transmitted to the piezoelectricelements for the touchpad actuation location. In embodiments herein, thehaptic feedback control signal may be sent to the same piezoelectricelement or elements that provided the electric charge actuation signal.Pursuant to the type of haptic feedback control signal send at adetermined voltage, current, or polarity being applied to thepiezoelectric material layer a corresponding type of haptic feedbackevent is generated by the piezoelectric element. Application of thehaptic feedback control signal to the piezoelectric material layercauses the piezoelectric material layer to warp upward and downward asdescribed above in embodiments herein to generate the type of hapticfeedback associated with selection of the Nth level depending uponactuation pressure applied. The generation of the type of hapticfeedback may create a haptic bump or click to be felt by the user at theactuation location on the extended action touchpad. In an exampleembodiment, the number of bumps or clicks may indicate the levelselected by the extended action touchpad actuation level applied. Forexample, a fast pulse of positive polarized voltage may generate ahaptic event that mimics a mechanical click of a touchpad mechanicalswitch in one example embodiment at a first level while two fast pulsesof voltage may generate a second type of haptic event that mimics afirst mechanical click followed by a second mechanical click in anexample embodiment. In a further embodiment, the second click may feelto a user as a deeper click than the first click. With this method 1200,from user actuation of the touchpad to haptic feedback creation, mayoccur within microseconds via the haptic touchpad controller. At thispoint the method may end, but as described herein the process may berepeated for each extended action touchpad actuation or for any extendedaction touchpad designated locations on the haptic touchpad.

The blocks of the flow diagrams of FIGS. 11 and 12 or steps and aspectsof the operation of the embodiments herein and discussed herein need notbe performed in any given or specified order. It is contemplated thatadditional blocks, steps, or functions may be added, some blocks, stepsor functions may not be performed, blocks, steps, or functions may occurcontemporaneously, and blocks, steps or functions from one flow diagrammay be performed within another flow diagram.

Devices, modules, resources, or programs that are in communication withone another need not be in continuous communication with each other,unless expressly specified otherwise. In addition, devices, modules,resources, or programs that are in communication with one another maycommunicate directly or indirectly through one or more intermediaries.

Although only a few exemplary embodiments have been described in detailherein, those skilled in the art will readily appreciate that manymodifications are possible in the exemplary embodiments withoutmaterially departing from the novel teachings and advantages of theembodiments of the present disclosure. Accordingly, all suchmodifications are intended to be included within the scope of theembodiments of the present disclosure as defined in the followingclaims. In the claims, means-plus-function clauses are intended to coverthe structures described herein as performing the recited function andnot only structural equivalents, but also equivalent structures.

The subject matter described herein is to be considered illustrative,and not restrictive, and the appended claims are intended to cover anyand all such modifications, enhancements, and other embodiments thatfall within the scope of the present invention. Thus, to the maximumextent allowed by law, the scope of the present invention is to bedetermined by the broadest permissible interpretation of the followingclaims and their equivalents and shall not be restricted or limited bythe foregoing detailed description.

What is claimed is:
 1. A haptic keyboard of an information handlingsystem, comprising: a coversheet to identify an extended action key ofthe haptic keyboard; a support layer; a contact foil placed between thecoversheet and the support layer; a piezoelectric element placed betweenthe contact foil and the support layer to receive an applied mechanicalstress at the extended action key of the coversheet and generate anelectric actuation signal; a controller of the information handlingsystem operatively coupled to the contact foil to: receive the electricactuation signal from the piezoelectric element placed under the appliedmechanical stress, via the contact foil, and determine a level of theapplied mechanical stress applied to the piezoelectric element from theelectric actuation signal; associate a selected alphanumeric characterfrom a plurality of alphanumeric characters associated with the actuatedextended action key based on the level of the applied mechanical stress;send a response haptic feedback control signal to the piezoelectricelement to cause the piezoelectric element to generate haptic feedbackat the extended action key corresponding to the selected alphanumericcharacter; and a processor of the information handling systemregistering a keystroke of the selected alphanumeric character.
 2. Thehaptic keyboard of claim 1, wherein the selected alphanumeric characteris a number.
 3. The haptic keyboard of claim 1, wherein the selectedalphanumeric character is a special character.
 4. The haptic keyboard ofclaim 1, wherein the selected alphanumeric character is a symbol.
 5. Thehaptic keyboard of claim 1, wherein the selected alphanumeric characteris a lower case letter at a first level of the applied mechanical stresson the extended action key.
 6. The haptic keyboard of claim 5, whereinthe selected alphanumeric character is an upper case letter at a secondlevel of the applied mechanical stress on the extended action key.
 7. Ahaptic keyboard of an information handling system, comprising: acoversheet to identify an extended action key of the haptic keyboard; asupport layer; a contact foil placed between the coversheet and thesupport layer; a piezoelectric element placed between the contact foiland the support layer to receive an applied mechanical stress at theextended action key of the coversheet and generate an electric actuationsignal; a controller of the information handling system operativelycoupled to the contact foil to: receive the electric actuation signalfrom the piezoelectric element placed under the applied mechanicalstress, via the contact foil, and determine a first level of the appliedmechanical stress applied to the piezoelectric element from the electricactuation signal; associate a selected first function or firstalphanumeric character from a plurality of functions or a plurality ofalphanumeric characters associated with the actuated extended actionkey, based on the first level of the applied mechanical stress; send afirst response haptic feedback control signal determined from aplurality of haptic feedback control signals corresponding to the firstfunction or the first alphanumeric character associated with theextended action key to the piezoelectric element to cause thepiezoelectric element to generate a first haptic feedback at theextended action key indicating the selected first function or the firstalphanumeric character; and a processor of the information handlingsystem registering a keystroke of the selected first function or thefirst alphanumeric character.
 8. The keyboard of claim 7, wherein thehaptic keyboard comprises fewer keys than a traditional QWERTY keyboard,and the plurality of alphanumeric characters includes each of aplurality of traditional alphanumeric characters displayed on thetraditional QWERTY keyboard.
 9. The keyboard of claim 7, wherein thehaptic keyboard comprises fewer keys than a traditional QWERTY keyboard,due to one or more extended action keys.
 10. The keyboard of claim 7,wherein the selection of the first function associated with the extendedaction key is displayed on a display screen to assist a user inselecting the first function from among the plurality of functions. 11.The keyboard of claim 7 further comprising: the controller to: determinea second level of the applied mechanical stress applied to thepiezoelectric element from the electric actuation signal; associate aselected second alphanumeric character from the plurality ofalphanumeric characters associated with the actuated extended actionkey, based on the second level of the applied mechanical stress; andsend a second response haptic feedback control signal determined fromthe plurality of haptic feedback control signals corresponding to thesecond alphanumeric character associated with the extended action key tothe piezoelectric element to cause the piezoelectric element to generatea second haptic feedback at the extended action key indicating theselected second alphanumeric character.
 12. The keyboard of claim 11,wherein the first alphanumeric character associated with the actuatedextended action key at the first level of the applied mechanical stressis a lower case letter and the second alphanumeric character associatedwith the actuated extended action key at the second level of the appliedmechanical stress is an upper case letter.
 13. The keyboard of claim 7,wherein the first alphanumeric character associated with the actuatedextended action key at the first level of the applied mechanical stressis a letter and the second alphanumeric character associated with theactuated extended action key at the second level of the appliedmechanical stress is a special character.
 14. The keyboard of claim 7further comprising: the controller to: determine a second level of theapplied mechanical stress applied to the piezoelectric element from theelectric actuation signal; associate a selected second function from theplurality of functions associated with the actuated extended action key,based on the second level of the applied mechanical stress; and send asecond response haptic feedback control signal determined from theplurality of haptic feedback control signals corresponding to the secondfunction associated with the extended action key to the piezoelectricelement to cause the piezoelectric element to generate a second hapticfeedback at the extended action key indicating the selected secondfunction.
 15. A haptic keyboard of an information handling system,comprising: a coversheet to identify an extended action key of thehaptic keyboard; a support layer; a contact foil placed between thecoversheet and the support layer; a piezoelectric element placed betweenthe contact foil and the support layer to receive an applied mechanicalstress at the extended action key of the coversheet and generate anelectric actuation signal; a controller of the information handlingsystem operatively coupled to the contact foil to: receive the electricactuation signal from the piezoelectric element placed under the appliedmechanical stress, via the contact foil, and determine a level of theapplied mechanical stress applied to the piezoelectric element from theelectric actuation signal; associate a selected first alphanumericcharacter from a plurality of alphanumeric characters associated withthe actuated extended action key, based on the first level of theapplied mechanical stress, wherein the actuated extended action key isassociated with more than one alphanumeric characters, based on aplurality of levels of the applied mechanical stress; and send oneresponse haptic feedback control signal determined from a plurality ofhaptic feedback control signals corresponding to the first alphanumericcharacters associated with the extended action key to the piezoelectricelement to cause the piezoelectric element to generate a first hapticfeedback at the extended action key indicating the first alphanumericcharacter.
 16. The keyboard of claim 15 further comprising: a processorof the information handling system registering a keystroke of the firstalphanumeric character.
 17. The keyboard of claim 15, wherein the haptickeyboard comprises fewer keys than a traditional QWERTY keyboard, due tothe extended action key.
 18. The keyboard of claim 15 furthercomprising: the controller to: determine a second level of the appliedmechanical stress applied to the piezoelectric element from the electricactuation signal; associate a selected second alphanumeric characterfrom the plurality of alphanumeric characters associated with theactuated extended action key, based on the second level of the appliedmechanical stress; and send a second response haptic feedback controlsignal determined from the plurality of haptic feedback control signalscorresponding to the second alphanumeric character associated with theextended action key to the piezoelectric element to cause thepiezoelectric element to generate a second haptic feedback at theextended action key indicating the selected second alphanumericcharacter.
 19. The keyboard of claim 18 further comprising: thecontroller to: determine a third level of the applied mechanical stressapplied to the piezoelectric element from the electric actuation signal;associate a selected third alphanumeric character from the plurality ofalphanumeric characters associated with the actuated extended actionkey, based on the third level of the applied mechanical stress; whereinthe first alphanumeric character is an upper case letter, the secondalphanumeric character is a lower case letter, and the thirdalphanumeric character is a special character; and send a third responsehaptic feedback control signal determined from the plurality of hapticfeedback control signals corresponding to the third alphanumericcharacter associated with the extended action key to the piezoelectricelement to cause the piezoelectric element to generate a third hapticfeedback at the extended action key indicating the selected thirdalphanumeric character.
 20. The keyboard of claim 15 further comprising:the controller to: determine a second level of the applied mechanicalstress applied to the piezoelectric element from the electric actuationsignal; associate a selected function from a plurality of functionsassociated with the actuated extended action key, based on a secondlevel of the applied mechanical stress; and send a second responsehaptic feedback control signal determined from the plurality of hapticfeedback control signals corresponding to the function associated withthe extended action key to the piezoelectric element to cause thepiezoelectric element to generate a second haptic feedback at theextended action key indicating the selected function.